Materialize | converting images to materials for use in video games

 by   BoundingBoxSoftware C# Version: Current License: GPL-3.0

kandi X-RAY | Materialize Summary

Materialize is a C# library. Materialize has no bugs, it has a Strong Copyleft License and it has medium support. However Materialize has 4 vulnerabilities. You can download it from GitHub.
Materialize is a program for converting images to materials for use in video games and whatnot
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                        summary
                        Materialize has a medium active ecosystem.
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                        It has 1154 star(s) with 180 fork(s). There are 71 watchers for this library.
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                        It had no major release in the last 6 months.
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                        There are 36 open issues and 1 have been closed. On average issues are closed in 15 days. There are 1 open pull requests and 0 closed requests.
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                        It has a neutral sentiment in the developer community.
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                        The latest version of Materialize is current.
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                                    Materialize has no bugs reported.
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                                                Materialize has 4 vulnerability issues reported (0 critical, 0 high, 4 medium, 0 low).
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                                                          kandi-License License

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                                                            Materialize is licensed under the GPL-3.0 License. This license is Strong Copyleft.
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                                                                        Materialize releases are not available. You will need to build from source code and install.
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                                                                                  Materialize Key Features

                                                                                  Materialize is a program for converting images to materials for use in video games and whatnot

                                                                                  Materialize Examples and Code Snippets

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                                                                                  Community Discussions

                                                                                  Trending Discussions on Materialize

                                                                                  Accessing Aurora Postgres Materialized Views from Glue data catalog for Glue Jobs
                                                                                  chevron right
                                                                                  transform file/directory structure into 'tree' in vue json
                                                                                  chevron right
                                                                                  Sliding window based on Akka actor source not behaving as expected
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                                                                                  QUESTION

                                                                                  Accessing Aurora Postgres Materialized Views from Glue data catalog for Glue Jobs
                                                                                  Asked 2021-Jun-15 at 13:51

                                                                                  I have an Aurora Serverless instance which has data loaded across 3 tables (mixture of standard and jsonb data types). We currently use traditional views where some of the deeply nested elements are surfaced along with other columns for aggregations and such.

                                                                                  We have two materialized views that we'd like to send to Redshift. Both the Aurora Postgres and Redshift are in Glue Catalog and while I can see Postgres views as a selectable table, the crawler does not pick up the materialized views.

                                                                                  Currently exploring two options to get the data to redshift.

                                                                                  1. Output to parquet and use copy to load
                                                                                  2. Point the Materialized view to jdbc sink specifying redshift.

                                                                                  Wanted recommendations on what might be most efficient approach if anyone has done a similar use case.

                                                                                  Questions:

                                                                                  1. In option 1, would I be able to handle incremental loads?
                                                                                  2. Is bookmarking supported for JDBC (Aurora Postgres) to JDBC (Redshift) transactions even if through Glue?
                                                                                  3. Is there a better way (other than the options I am considering) to move the data from Aurora Postgres Serverless (10.14) to Redshift.

                                                                                  Thanks in advance for any guidance provided.

                                                                                  ANSWER

                                                                                  Answered 2021-Jun-15 at 13:51

                                                                                  Went with option 2. The Redshift Copy/Load process writes csv with manifest to S3 in any case so duplicating that is pointless.

                                                                                  Regarding the Questions:

                                                                                  1. N/A

                                                                                  2. Job Bookmarking does work. There is some gotchas though - ensure Connections both to RDS and Redshift are present in Glue Pyspark job, IAM self ref rules are in place and to identify a row that is unique [I chose the primary key of underlying table as an additional column in my materialized view] to use as the bookmark.

                                                                                  3. Using the primary key of core table may buy efficiencies in pruning materialized views during maintenance cycles. Just retrieve latest bookmark from cli using aws glue get-job-bookmark --job-name yourjobname and then just that in the where clause of the mv as where id >= idinbookmark

                                                                                    conn = glueContext.extract_jdbc_conf("yourGlueCatalogdBConnection") connection_options_source = { "url": conn['url'] + "/yourdB", "dbtable": "table in dB", "user": conn['user'], "password": conn['password'], "jobBookmarkKeys":["unique identifier from source table"], "jobBookmarkKeysSortOrder":"asc"}

                                                                                  datasource0 = glueContext.create_dynamic_frame.from_options(connection_type="postgresql", connection_options=connection_options_source, transformation_ctx="datasource0")

                                                                                  That's all, folks

                                                                                  Source https://stackoverflow.com/questions/67928401

                                                                                  QUESTION

                                                                                  transform file/directory structure into 'tree' in vue json
                                                                                  Asked 2021-Jun-15 at 01:45

                                                                                  transform file/directory structure into 'tree' in vue json

                                                                                  I have an array of objects that looks like this:

                                                                                  [
                                                                                      {
                                                                                          "name": "Officer",
                                                                                          "isDirectory": true,
                                                                                          "path": "Officer/EventReport/SelfReport/110-04-02/DADF.pdf"
                                                                                      },
                                                                                      {
                                                                                          "name": "Officer",
                                                                                          "isDirectory": true,
                                                                                          "path": "Officer/EventReport/SelfReport/110-04-10/110010.pdf"
                                                                                      },
                                                                                      {
                                                                                          "name": "Officer",
                                                                                          "isDirectory": true,
                                                                                          "path": "Officer/S_Meeting/W_Meeting/110-5/Officer_from.docx"
                                                                                      },
                                                                                      {
                                                                                          "name": "Officer",
                                                                                          "isDirectory": true,
                                                                                          "path": "Officer/S_Meeting/W_Meeting/110-5/1620021359034.jpg"
                                                                                      },
                                                                                      {
                                                                                          "name": "Officer",
                                                                                          "isDirectory": true,
                                                                                          "path": "Officer/S_Meeting/W_Meeting/110-5/2021-05-18_092810.png"
                                                                                      }
                                                                                  ]
                                                                                  

                                                                                  There could be any number of arbitrary path's, this is the result of iterating through files and folders within a directory.

                                                                                  What I'm trying to do is determine the 'root' node of these. Ultimately, this will be stored in mongodb and use materialized path to determine it's relationships.

                                                                                  I hope I can show this one.

                                                                                  [
                                                                                      {
                                                                                          "name": "Officer",   //part1
                                                                                          "isDirectory": true,
                                                                                          "items": [
                                                                                              {
                                                                                                  "name": "EventReport",  //part2
                                                                                                  "isDirectory": true,
                                                                                                  "items": [
                                                                                                      {
                                                                                                          "name": "SelfReport",  //part3
                                                                                                          "isDirectory": true,
                                                                                                          "items": [
                                                                                                              {
                                                                                                                  "name": "2020-110-04-02",  //part4
                                                                                                                  "isDirectory": true,
                                                                                                                  "items": [
                                                                                                                      {
                                                                                                                          "name": "RCBS.pdf",  // name
                                                                                                                          "isDirectory": false
                                                                                                                      }
                                                                                                                  ]
                                                                                                              },
                                                                                                              {
                                                                                                                  "name": "2020-110-04-10",  //part4 
                                                                                                                  "isDirectory": true,
                                                                                                                  "items": [
                                                                                                                      {
                                                                                                                          "name": "1100_b.pdf",  //name
                                                                                                                          "isDirectory": false
                                                                                                                      }
                                                                                                                  ]
                                                                                                              }
                                                                                                          ]
                                                                                                      }
                                                                                                  ]
                                                                                              },
                                                                                              {
                                                                                                  "name": "SecurityMeeting",  // part2
                                                                                                  "isDirectory": true,
                                                                                                  "items": [
                                                                                                      {
                                                                                                          "name": "SecurityWorkMeeting",  //part3
                                                                                                          "isDirectory": true,
                                                                                                          "items": [
                                                                                                              {
                                                                                                                  "name": "2021-05-SecurityWorkMeeting",  //part4
                                                                                                                  "isDirectory": true,
                                                                                                                  "items": [
                                                                                                                      {
                                                                                                                          "name": "Officer_Report.docx",  //name
                                                                                                                          "isDirectory": false
                                                                                                                      },
                                                                                                                      {
                                                                                                                          "name": "16200.jpg",  //name
                                                                                                                          "isDirectory": false
                                                                                                                      },
                                                                                                                      {
                                                                                                                          "name": "2021-05-18_2342.png",  //name
                                                                                                                          "isDirectory": false
                                                                                                                      }
                                                                                                                  ]
                                                                                                              },      
                                                                                                          ]
                                                                                                      }
                                                                                                  ]
                                                                                              }
                                                                                          ]
                                                                                      },    
                                                                                  ]
                                                                                  

                                                                                  method

                                                                                  let arr = xhr.data.UploadFile;
                                                                                  let tree = {};
                                                                                  
                                                                                  arr.forEach(item => {
                                                                                    let tokens = item.path.replace(/^\/|\/$/g, "").split("/");
                                                                                    let current = tree;
                                                                                    for (let i=0; i {
                                                                                      if (Object.keys(node[key]).length === 0) {
                                                                                        return {
                                                                                          isDirectory: false,
                                                                                          name: key,
                                                                                        };
                                                                                      }
                                                                                      return {
                                                                                        isDirectory: true,
                                                                                        name: key,
                                                                                        items: parseNode(node[key]),
                                                                                      };
                                                                                    });
                                                                                  };
                                                                                  let result = parseNode(tree);
                                                                                  console.log("RESULT", result);
                                                                                  

                                                                                  update enter image description here

                                                                                  I dont know why it will pass the parseNode = function(node), and cannot get result. And the items should be use array. Like this one

                                                                                  [
                                                                                      {
                                                                                          "name": "Officer",   //part1
                                                                                          "isDirectory": true,
                                                                                          "items": [
                                                                                              {
                                                                                                  "name": "EventReport",  //part2
                                                                                                  "isDirectory": true,
                                                                                                  "items": [
                                                                                                      {
                                                                                                          "name": "SelfReport",  //part3
                                                                                                          "isDirectory": true,
                                                                                                          "items": [
                                                                                                              {
                                                                                                                  "name": "2020-110-04-02",  //part4
                                                                                                                  "isDirectory": true,
                                                                                                                  "items": [
                                                                                                                      {
                                                                                                                          "name": "RCBS.pdf",  // name
                                                                                                                          "isDirectory": false
                                                                                                                      }
                                                                                                                  ]
                                                                                                              },
                                                                                                              {
                                                                                                                  "name": "2020-110-04-10",  //part4 
                                                                                                                  "isDirectory": true,
                                                                                                                  "items": [
                                                                                                                      {
                                                                                                                          "name": "1100_b.pdf",  //name
                                                                                                                          "isDirectory": false
                                                                                                                      }
                                                                                                                  ]
                                                                                                              }
                                                                                                          ]
                                                                                                      }
                                                                                                  ]
                                                                                              },
                                                                                              {
                                                                                                  "name": "SecurityMeeting",  // part2
                                                                                                  "isDirectory": true,
                                                                                                  "items": [
                                                                                                      {
                                                                                                          "name": "SecurityWorkMeeting",  //part3
                                                                                                          "isDirectory": true,
                                                                                                          "items": [
                                                                                                              {
                                                                                                                  "name": "2021-05-SecurityWorkMeeting",  //part4
                                                                                                                  "isDirectory": true,
                                                                                                                  "items": [
                                                                                                                      {
                                                                                                                          "name": "Officer_Report.docx",  //name
                                                                                                                          "isDirectory": false
                                                                                                                      },
                                                                                                                      {
                                                                                                                          "name": "16200.jpg",  //name
                                                                                                                          "isDirectory": false
                                                                                                                      },
                                                                                                                      {
                                                                                                                          "name": "2021-05-18_2342.png",  //name
                                                                                                                          "isDirectory": false
                                                                                                                      }
                                                                                                                  ]
                                                                                                              },      
                                                                                                          ]
                                                                                                      }
                                                                                                  ]
                                                                                              }
                                                                                          ]
                                                                                      },    
                                                                                  ]
                                                                                  

                                                                                  ANSWER

                                                                                  Answered 2021-Jun-11 at 09:55

                                                                                  EDIT

                                                                                  Here is the full implementation, based upon my initial answer. I changed the forEach() into map() as it is more suitable in this case.

                                                                                  let arr = xhr.data.UploadFile;
                                                                                  let tree = {};
                                                                                  
                                                                                  arr.forEach(item => {
                                                                                    let tokens = item.path.replace(/^\/|\/$/g, "").split("/");
                                                                                    let current = tree;
                                                                                    for (let i=0; i {
                                                                                      if (Object.keys(node[key]).length === 0) {
                                                                                        return {
                                                                                          isDirectory: false,
                                                                                          name: key,
                                                                                        };
                                                                                      }
                                                                                      return {
                                                                                        isDirectory: true,
                                                                                        name: key,
                                                                                        items: parseNode(node[key]),
                                                                                      };
                                                                                    });
                                                                                  };
                                                                                  let result = parseNode(tree);
                                                                                  console.log("RESULT", result);
                                                                                  

                                                                                  ORIGINAL ANSWER

                                                                                  You could build a map by iterating on the array (I named it data):

                                                                                  let tree = {};
                                                                                  data.forEach(item => {
                                                                                    let tokens = item.path.split("/");
                                                                                    let current = tree;
                                                                                    for (let i=0; i

                                                                                  Then, walk through your map to build your result array:

                                                                                  const parseNode = function(node) {
                                                                                    let res = [];
                                                                                    Object.keys(node).forEach(key => {
                                                                                      if (Object.keys(node[key]).length === 0) {
                                                                                        res.push({
                                                                                          isDirectory: false,
                                                                                          name: key,
                                                                                        });
                                                                                      } else {
                                                                                        res.push({
                                                                                          isDirectory: true,
                                                                                          name: key,
                                                                                          items: parseNode(node[key]),
                                                                                        });
                                                                                      }
                                                                                    });
                                                                                    return res;
                                                                                  };
                                                                                  let result = parseNode(tree);
                                                                                  

                                                                                  Source https://stackoverflow.com/questions/67915991

                                                                                  QUESTION

                                                                                  Sliding window based on Akka actor source not behaving as expected
                                                                                  Asked 2021-Jun-14 at 16:30

                                                                                  Using below code I'm attempting to use an actor as a source and send messages of type Double to be processed via a sliding window.

                                                                                  The sliding windows is defined as sliding(2, 2) to calculate each sequence of twp values sent.

                                                                                  Sending the message:

                                                                                          actorRef.tell(10, ActorRef.noSender());
                                                                                          actorRef.tell(20, ActorRef.noSender());
                                                                                          actorRef.tell(30, ActorRef.noSender());
                                                                                          actorRef.tell(40, ActorRef.noSender());
                                                                                          actorRef.tell(20, ActorRef.noSender());
                                                                                  

                                                                                  Should calculate the average as follows :

                                                                                  10 + 20 / 2 = 15
                                                                                  30 + 40 / 2 = 35
                                                                                  

                                                                                  But the calculation does not appear to be invoked in below code.

                                                                                  Here I output the value :

                                                                                      movingAverage.runForeach(n -> {
                                                                                          if( n > 0){
                                                                                              System.out.println(n);
                                                                                          }
                                                                                      }, system);
                                                                                  

                                                                                  src code:

                                                                                  import akka.Done;
                                                                                  import akka.actor.ActorRef;
                                                                                  import akka.stream.CompletionStrategy;
                                                                                  import akka.stream.OverflowStrategy;
                                                                                  import akka.stream.javadsl.Sink;
                                                                                  import akka.stream.javadsl.Source;
                                                                                  
                                                                                  import java.util.Optional;
                                                                                  
                                                                                  public class FilterThreshold {
                                                                                  
                                                                                      public static void main(String[] args) {
                                                                                  
                                                                                          final akka.actor.ActorSystem system = akka.actor.ActorSystem.create("Source");
                                                                                  
                                                                                          final int bufferSize = 1;
                                                                                          final Source source =
                                                                                                  Source.actorRef(
                                                                                                          elem -> {
                                                                                                              // complete stream immediately if we send it Done
                                                                                                              if (elem == Done.done()) {
                                                                                                                  return Optional.of(CompletionStrategy.immediately());
                                                                                                              } else {
                                                                                                                  return Optional.empty();
                                                                                                              }
                                                                                                          },
                                                                                                          // never fail the stream because of a message
                                                                                                          elem -> Optional.empty(),
                                                                                                          bufferSize,
                                                                                                          OverflowStrategy.dropHead());
                                                                                          ActorRef actorRef = source.to(Sink.foreach(System.out::println)).run(system);
                                                                                  
                                                                                          actorRef.tell(10, ActorRef.noSender());
                                                                                          actorRef.tell(20, ActorRef.noSender());
                                                                                          actorRef.tell(30, ActorRef.noSender());
                                                                                          actorRef.tell(40, ActorRef.noSender());
                                                                                          actorRef.tell(20, ActorRef.noSender());
                                                                                  
                                                                                          Source movingAverage = source
                                                                                                  .sliding(2, 2)
                                                                                                  .map(window -> (window.stream().mapToDouble(i -> i).sum()) / window.size());
                                                                                  
                                                                                  
                                                                                          movingAverage.runForeach(n -> {
                                                                                              if( n > 0){
                                                                                                  System.out.println(n);
                                                                                              }
                                                                                          }, system);
                                                                                  
                                                                                      }
                                                                                  }
                                                                                  

                                                                                  I've edited the code from https://doc.akka.io/docs/akka/current/stream/operators/Source-or-Flow/sliding.html

                                                                                  How to apply the sliding window function defined as movingAverage to calculate the values sent via the Akka actor actorRef ?

                                                                                  Update:

                                                                                  The method permaterialize takes an actor system as a parameter.

                                                                                  Updating the code from:

                                                                                  final Pair> prematPair = source.preMaterialize();
                                                                                  

                                                                                  to:

                                                                                  final Pair> prematPair = source.preMaterialize(system);
                                                                                  

                                                                                  results in a compile time error:

                                                                                  Required type:
                                                                                  Pair
                                                                                  >
                                                                                  
                                                                                  Provided:
                                                                                  Pair
                                                                                  >
                                                                                  

                                                                                  Is there an alternative method I should use ?

                                                                                  Updated code posted:

                                                                                  import akka.Done;
                                                                                  import akka.NotUsed;
                                                                                  import akka.actor.ActorRef;
                                                                                  import akka.japi.Pair;
                                                                                  import akka.stream.CompletionStrategy;
                                                                                  import akka.stream.OverflowStrategy;
                                                                                  import akka.stream.javadsl.Flow;
                                                                                  import akka.stream.javadsl.Source;
                                                                                  
                                                                                  import java.util.Optional;
                                                                                  
                                                                                  public class FilterThreshold {
                                                                                  
                                                                                      public static void main(String[] args) {
                                                                                  
                                                                                          final akka.actor.ActorSystem system = akka.actor.ActorSystem.create("Source");
                                                                                  
                                                                                          final int bufferSize = 1;
                                                                                          final Source source =
                                                                                                  Source.actorRef(
                                                                                                          elem -> {
                                                                                                              System.out.println("elem is "+elem);
                                                                                                              // complete stream immediately if we send it Done
                                                                                                              if (elem == Done.done()) {
                                                                                                                  return Optional.of(CompletionStrategy.immediately());
                                                                                                              } else {
                                                                                                                  return Optional.empty();
                                                                                                              }
                                                                                                          },
                                                                                                          // never fail the stream because of a message
                                                                                                          elem -> Optional.empty(),
                                                                                                          bufferSize,
                                                                                                          OverflowStrategy.dropHead());
                                                                                  
                                                                                          // source is as before
                                                                                          final Pair> prematPair = source.preMaterialize(system);
                                                                                  
                                                                                          Flow movingAverageFlow =
                                                                                                  Flow.of(Double.class)
                                                                                                          .sliding(2, 2)
                                                                                                          .map(window -> (window.stream().mapToDouble(i -> i).sum()) / window.size());
                                                                                  
                                                                                          final Source prematSource = prematPair.second();
                                                                                  
                                                                                          prematSource.via(movingAverageFlow).runForeach(n -> {
                                                                                              System.out.println("n is "+n);
                                                                                              if (n > 0) {
                                                                                                  System.out.println(n);
                                                                                              }
                                                                                          }, system);
                                                                                  
                                                                                          final ActorRef actorRef = prematPair.first();
                                                                                  
                                                                                          actorRef.tell(10, ActorRef.noSender());
                                                                                          actorRef.tell(20, ActorRef.noSender());
                                                                                          actorRef.tell(20, ActorRef.noSender());
                                                                                          actorRef.tell(20, ActorRef.noSender());
                                                                                          actorRef.tell(20, ActorRef.noSender());
                                                                                  
                                                                                      }
                                                                                  }
                                                                                  

                                                                                  Update2 :

                                                                                  Using code :

                                                                                  import akka.Done;
                                                                                  import akka.NotUsed;
                                                                                  import akka.actor.ActorRef;
                                                                                  import akka.japi.Pair;
                                                                                  import akka.stream.CompletionStrategy;
                                                                                  import akka.stream.OverflowStrategy;
                                                                                  import akka.stream.javadsl.Flow;
                                                                                  import akka.stream.javadsl.Source;
                                                                                  
                                                                                  import java.util.Optional;
                                                                                  
                                                                                  public class FilterThreshold {
                                                                                  
                                                                                      public static void main(String[] args) {
                                                                                  
                                                                                          final akka.actor.ActorSystem system = akka.actor.ActorSystem.create("Source");
                                                                                  
                                                                                          final int bufferSize = 1;
                                                                                          final Source source =
                                                                                                  Source.actorRef(
                                                                                                          elem -> {
                                                                                                              System.out.println("elem is "+elem);
                                                                                                              // complete stream immediately if we send it Done
                                                                                                              if (elem == Done.done()) {
                                                                                                                  return Optional.of(CompletionStrategy.immediately());
                                                                                                              } else {
                                                                                                                  return Optional.empty();
                                                                                                              }
                                                                                                          },
                                                                                                          // never fail the stream because of a message
                                                                                                          elem -> Optional.empty(),
                                                                                                          bufferSize,
                                                                                                          OverflowStrategy.dropHead());
                                                                                  
                                                                                          // source is as before
                                                                                          final Pair> prematPair = source.preMaterialize(system);
                                                                                          final ActorRef actorRef = prematPair.first();
                                                                                          final Source prematSource = prematPair.second();
                                                                                  
                                                                                          Flow movingAverageFlow =
                                                                                                  Flow.of(Double.class)
                                                                                                          .sliding(2, 2)
                                                                                                          .map(window -> (window.stream().mapToDouble(i -> i).sum()) / window.size());
                                                                                  
                                                                                          prematSource.via(movingAverageFlow).runForeach(n -> {
                                                                                              System.out.println("n is "+n);
                                                                                              if (n > 0) {
                                                                                                  System.out.println(n);
                                                                                              }
                                                                                          }, system);
                                                                                  
                                                                                          actorRef.tell(10, ActorRef.noSender());
                                                                                          actorRef.tell(20, ActorRef.noSender());
                                                                                          actorRef.tell(20, ActorRef.noSender());
                                                                                          actorRef.tell(20, ActorRef.noSender());
                                                                                          actorRef.tell(20, ActorRef.noSender());
                                                                                  
                                                                                          prematSource.run(system);
                                                                                  
                                                                                      }
                                                                                  }
                                                                                  

                                                                                  prints:

                                                                                  elem is 10
                                                                                  elem is 20
                                                                                  elem is 20
                                                                                  elem is 20
                                                                                  elem is 20
                                                                                  

                                                                                  So it seems the messages are being sent correctly but the moving average is not being materialized.

                                                                                  Is using prematSource.run(system); not the correct way to materialize the value ?

                                                                                  ANSWER

                                                                                  Answered 2021-Jun-14 at 11:39

                                                                                  The short answer is that your source is a recipe of sorts for materializing a Source and each materialization ends up being a different source.

                                                                                  In your code, source.to(Sink.foreach(System.out::println)).run(system) is one stream with the materialized actorRef being only connected to this stream, and

                                                                                  movingAverage.runForeach(n -> {
                                                                                      if( n > 0){
                                                                                          System.out.println(n);
                                                                                      }
                                                                                  }, system);
                                                                                  

                                                                                  is a completely separate stream with a different materialized ActorRef (which ultimately gets thrown away since runForeach materializes as a CompletionStage.

                                                                                  When dealing with Source.actorRef, it's often a good idea to prematerialize the source before running the stream:

                                                                                  import akka.NotUsed
                                                                                  import akka.japi.Pair
                                                                                  import akka.stream.javadsl.Flow
                                                                                  
                                                                                  // source is as before
                                                                                  final Pair> prematPair = source.preMaterialize(system);
                                                                                  final ActorRef actorRef = prematPair.first();
                                                                                  final Source prematSource = prematPair.second();
                                                                                  
                                                                                  Flow movingAverageFlow =
                                                                                      Flow.of(Double.class)
                                                                                          .sliding(2, 2)
                                                                                          .map(window -> (window.stream().mapToDouble(i -> i).sum()) / window.size());
                                                                                  
                                                                                  prematSource.via(movingAverageFlow).runForeach(n -> {
                                                                                      if (n > 0) {
                                                                                        System.out.println(n);
                                                                                      }
                                                                                  }, system);
                                                                                  

                                                                                  (Apologies, my Java is quite rusty)

                                                                                  Source https://stackoverflow.com/questions/67961179

                                                                                  QUESTION

                                                                                  System.InvalidOperationException: Invalid attempt to call FieldCount when reader is closed
                                                                                  Asked 2021-Jun-12 at 22:45
                                                                                  1. I would have expected the queryOutput to be materialized?
                                                                                  2. Why is there the invalid attempt to call fieldcount when it alreadyhas the IEnumerable?
                                                                                  /// 
                                                                                     /// Get all columns for a certain table
                                                                                     /// 
                                                                                     public async Task>> GetAllColumnsFromTableAsync(string tableName)
                                                                                  {
                                                                                      List> result;
                                                                                      string query = "SELECT COLUMN_NAME, DATA_TYPE, CHARACTER_MAXIMUM_LENGTH FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME= @tableName";
                                                                                      using (IDbConnection db = DbConnection) 
                                                                                      { 
                                                                                          IEnumerable> queryOutput = await db.QueryAsync>
                                                                                              (query, Tuple.Create, new { tableName = tableName }, null, false, splitOn: "*");
                                                                                          result = queryOutput.ToList(); // System.InvalidOperationException: Invalid attempt to call FieldCount when reader is closed.
                                                                                      }
                                                                                  
                                                                                      if (result is not null && result.Count > 0)
                                                                                      {
                                                                                          return result;
                                                                                      }
                                                                                      else
                                                                                      {
                                                                                          return default;
                                                                                      }
                                                                                  }
                                                                                  
                                                                                  • making this a non async method works. so it MUST be "tuple"+"dapper"+"async"

                                                                                  ref: https://github.com/DapperLib/Dapper/issues/745

                                                                                  update:

                                                                                  1. when replacing the tuple with named tuples the query in itself works.

                                                                                  public async Task<(string COLUMN_NAME, string DATA_TYPE, int? CHARACTER_MAXIMUM_LENGTH)>> GetAllColumnsFromTableAsync2(string tableName)
                                                                                  {
                                                                                      const string query = "SELECT COLUMN_NAME, DATA_TYPE, CHARACTER_MAXIMUM_LENGTH FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME= @tableName";
                                                                                      using var connection = new SqlConnection(_connectionstring);
                                                                                      var output = await connection.QueryAsync<(string COLUMN_NAME, string DATA_TYPE, int? CHARACTER_MAXIMUM_LENGTH)>
                                                                                              (query, new { tableName = tableName });
                                                                                      return output.ToList();
                                                                                  }
                                                                                  

                                                                                  I have a further problem but that is another question.

                                                                                  ANSWER

                                                                                  Answered 2021-Jun-12 at 20:53

                                                                                  Dapper's supposed to make your life easier, and that code looks complicated.

                                                                                  If you use a Tuple with named fields, you can just use Dapper's auto mapping to materialize. EG:

                                                                                  static class DbExtensions
                                                                                  {
                                                                                      public static async Task<(string COLUMN_NAME, string DATA_TYPE, int? CHARACTER_MAXIMUM_LENGTH)>> GetAllColumnsFromTableAsync(this IDbConnection db, string tableName, string schema = "dbo")
                                                                                      {
                                                                                          string query = "SELECT COLUMN_NAME, DATA_TYPE, CHARACTER_MAXIMUM_LENGTH FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME= @tableName and TABLE_SCHEMA=@schema";
                                                                                          var queryOutput = await db.QueryAsync<(string COLUMN_NAME, string DATA_TYPE, int? CHARACTER_MAXIMUM_LENGTH)>(query, new { tableName = tableName, schema = schema });
                                                                                          return queryOutput.ToList();
                                                                                      }
                                                                                  }
                                                                                  

                                                                                  Also note there's a bug in your query if you have multiple tables with the same name, so you should specify the schema.

                                                                                  Source https://stackoverflow.com/questions/67952549

                                                                                  QUESTION

                                                                                  Evaluate simple RNN in Julia Flux
                                                                                  Asked 2021-Jun-11 at 12:27

                                                                                  I'm trying to learn Recurrent Neural Networks (RNN) with Flux.jl in Julia by following along some tutorials, like Char RNN from the FluxML/model-zoo.

                                                                                  I managed to build and train a model containing some RNN cells, but am failing to evaluate the model after training.

                                                                                  Can someone point out what I'm missing for this code to evaluate a simple (untrained) RNN?

                                                                                  julia> using Flux
                                                                                  julia> simple_rnn = Flux.RNN(1, 1, (x -> x))
                                                                                  julia> simple_rnn.([1, 2, 3])
                                                                                  
                                                                                  ERROR: MethodError: no method matching (::Flux.RNNCell{var"#1#2", Matrix{Float32}, Vector{Float32}, Matrix{Float32}})(::Matrix{Float32}, ::Int64)
                                                                                  Closest candidates are:
                                                                                    (::Flux.RNNCell{F, A, V, var"#s263"} where var"#s263"<:AbstractMatrix{T})(::Any, ::Union{AbstractMatrix{T}, AbstractVector{T}, Flux.OneHotArray}) where {F, A, V, T} at C:\Users\UserName\.julia\packages\Flux\6o4DQ\src\layers\recurrent.jl:83
                                                                                  Stacktrace:
                                                                                   [1] (::Flux.Recur{Flux.RNNCell{var"#1#2", Matrix{Float32}, Vector{Float32}, Matrix{Float32}}, Matrix{Float32}})(x::Int64)
                                                                                     @ Flux C:\Users\UserName\.julia\packages\Flux\6o4DQ\src\layers\recurrent.jl:34
                                                                                   [2] _broadcast_getindex_evalf
                                                                                     @ .\broadcast.jl:648 [inlined]
                                                                                   [3] _broadcast_getindex
                                                                                     @ .\broadcast.jl:621 [inlined]
                                                                                   [4] getindex
                                                                                     @ .\broadcast.jl:575 [inlined]
                                                                                   [5] copy
                                                                                     @ .\broadcast.jl:922 [inlined]
                                                                                   [6] materialize(bc::Base.Broadcast.Broadcasted{Base.Broadcast.DefaultArrayStyle{1}, Nothing, Flux.Recur{Flux.RNNCell{var"#1#2", Matrix{Float32}, Vector{Float32}, Matrix{Float32}}, Matrix{Float32}}, Tuple{Vector{Int64}}})
                                                                                     @ Base.Broadcast .\broadcast.jl:883
                                                                                   [7] top-level scope
                                                                                     @ REPL[3]:1
                                                                                   [8] top-level scope
                                                                                     @ C:\Users\UserName\.julia\packages\CUDA\LTbUr\src\initialization.jl:81
                                                                                  

                                                                                  I'm using Julia 1.6.1 on Windows 10.

                                                                                  ANSWER

                                                                                  Answered 2021-Jun-11 at 12:27

                                                                                  Turns out it's just a problem with the input type.

                                                                                  Doing something like this will work:

                                                                                  julia> v = Vector{Vector{Float32}}([[1], [2], [3]])
                                                                                  julia> simple_rnn.(v)
                                                                                  3-element Vector{Vector{Float32}}:
                                                                                   [9.731078]
                                                                                   [16.657223]
                                                                                   [28.398548]
                                                                                  

                                                                                  I tried a lot of combinations until I found the working one. There is probably a way to automatically convert the input with some evaluation function.

                                                                                  Source https://stackoverflow.com/questions/67934386

                                                                                  QUESTION

                                                                                  CQRS: Can the write model consume a read model?
                                                                                  Asked 2021-Jun-11 at 07:38

                                                                                  When reading about CQRS it is often mentioned that the write model should not depend on any read model (assuming there is one write model and up to N read models). This makes a lot of sense, especially since read models usually only become eventually consistent with the write model. Also, we should be able to change or replace read models without breaking the write model.

                                                                                  However, read models might contain valuable information that is aggregated across many entities of the write model. These aggregations might even contain non-trivial business rules. One can easily imagine a business policy that evaluates a piece of information that a read model possesses, and in reaction to that changes one or many entities via the write model. But where should this policy be located/implemented? Isn't this critical business logic that tightly couples information coming from one particular read model with the write model?

                                                                                  When I want to implement said policy without coupling the write model to the read model, I can imagine the following strategy: Include a materialized view in the write model that gets updated synchronously whenever a relevant part of the involved entities changes (when using DDD, this could be done via domain events). However, this denormalizes the write model, and is effectively a special read model embedded in the write model itself.

                                                                                  I can imagine that DDD purists would say that such a policy should not exist, because it represents a business invariant/rule that encompasses multiple entities (a.k.a. aggregates). I could probably agree in theory, but in practice, I often encounter such requirements anyway.

                                                                                  Finally, my question is simply: How do you deal with requirements that change data in reaction to certain conditions whose evaluation requires a read model?

                                                                                  ANSWER

                                                                                  Answered 2021-Jun-07 at 01:20

                                                                                  First, any write model which validates commands is a read model (because at some point validating a command requires a read), albeit one that is optimized for the purpose of validating commands. So I'm not sure where you're seeing that a write model shouldn't depend on a read model.

                                                                                  Second, a domain event is implicitly a command to the consumers of the event: "process/consider/incorporate this event", in which case a write model processor can subscribe to the events arising from a different write model: from the perspective of the subscribing write model, these are just commands.

                                                                                  Source https://stackoverflow.com/questions/67863289

                                                                                  QUESTION

                                                                                  Webpage using appScript: innerHTML assignment not working
                                                                                  Asked 2021-Jun-09 at 22:03

                                                                                  I have a simple WebApp application that reads the data from google sheet and displays in HTML using materialize css( 1.0.0), JS. I am new to this stack of tools. HTML page has 2 containers and bottom one supposed to be populated (using innerHTML assignment)based on the selection on the top container. The bottom container content is simple card contents in table format. I want to put a HTML Select object with List of values to be displayed and created a Appscript function. I am assigning the function output to innerHTML like this. -- JS

                                                                                    function generateCards(text_card){
                                                                                        document.getElementById("container-id").innerHTML += text_card;
                                                                                    }
                                                                                  
                                                                                        function createAuthorCards(authorName) {
                                                                                        document.getElementById("container-id").innerHTML = "";
                                                                                        google.script.run.withSuccessHandler(generateCards).getCardDynamicText(authorName) ;
                                                                                  
                                                                                      }

                                                                                  -- If put copy/paste the function output in HTML it works( goes through rendering when refereshing), but if i use InnerHTML, the listbox is disabled, but all else seems ok. needed imageplease see the 2 attachments needed and missing_listbox images.enter image description here Is there any limitations of using innerHTML in webApp?

                                                                                  ANSWER

                                                                                  Answered 2021-Jun-09 at 22:03

                                                                                  I was using google Webapp. It looks google doesn't allow the editing of dynamically created items. So I ended up using Modals to make the selections and save it.

                                                                                  Source https://stackoverflow.com/questions/67764340

                                                                                  QUESTION

                                                                                  Strange mobile css behavior
                                                                                  Asked 2021-Jun-09 at 12:02

                                                                                  I have a basic CSS photo gallery that works pretty well on desktop devices, and works well also if I simulate a mobile view in Mozilla Responsive Design Mode or this CodePen but doesn't seems to work properly on real mobile devices.

                                                                                  :root {
                                                                                    --blue: #6483B2ff;
                                                                                    --dark-blue: #1d3557;
                                                                                    --light-blue: #e1e5f2;
                                                                                    --white: #ffffff;
                                                                                    --flag-blue: #0038B8;
                                                                                    --error: #660000;
                                                                                  }
                                                                                  
                                                                                  #gallery {
                                                                                    margin: 3em 0;
                                                                                    display: -webkit-box;
                                                                                    display: -ms-flexbox;
                                                                                    display: flex;
                                                                                    -webkit-box-orient: vertical;
                                                                                    -webkit-box-direction: normal;
                                                                                        -ms-flex-direction: column;
                                                                                            flex-direction: column;
                                                                                    -webkit-box-pack: center;
                                                                                        -ms-flex-pack: center;
                                                                                            justify-content: center;
                                                                                    -webkit-box-align: center;
                                                                                        -ms-flex-align: center;
                                                                                            align-items: center;
                                                                                  }
                                                                                  
                                                                                  #gallery .quote {
                                                                                    text-align: center;
                                                                                  }
                                                                                  
                                                                                  #gallery .gallery-layout {
                                                                                    display: -webkit-box;
                                                                                    display: -ms-flexbox;
                                                                                    display: flex;
                                                                                    -webkit-box-orient: horizontal;
                                                                                    -webkit-box-direction: normal;
                                                                                        -ms-flex-direction: row;
                                                                                            flex-direction: row;
                                                                                    background: var(--light-blue);
                                                                                    border-radius: 15px;
                                                                                    width: 100%;
                                                                                    -webkit-box-pack: justify;
                                                                                        -ms-flex-pack: justify;
                                                                                            justify-content: space-between;
                                                                                    -webkit-box-align: center;
                                                                                        -ms-flex-align: center;
                                                                                            align-items: center;
                                                                                    padding: 0 20px;
                                                                                  }
                                                                                  
                                                                                  #gallery .gallery-layout #gallery-items {
                                                                                    display: none;
                                                                                  }
                                                                                  
                                                                                  #gallery .gallery-layout .frame {
                                                                                    display: -webkit-box;
                                                                                    display: -ms-flexbox;
                                                                                    display: flex;
                                                                                    position: relative;
                                                                                  }
                                                                                  
                                                                                  #gallery .gallery-layout .frame .overlay {
                                                                                    display: -webkit-box;
                                                                                    display: -ms-flexbox;
                                                                                    display: flex;
                                                                                    -webkit-box-pack: center;
                                                                                        -ms-flex-pack: center;
                                                                                            justify-content: center;
                                                                                    -webkit-box-align: center;
                                                                                        -ms-flex-align: center;
                                                                                            align-items: center;
                                                                                    position: absolute;
                                                                                    width: 100%;
                                                                                    height: auto;
                                                                                    background: rgba(0, 0, 0, 0.5);
                                                                                    bottom: 0;
                                                                                    left: 0;
                                                                                  }
                                                                                  
                                                                                  #gallery .gallery-layout .frame .overlay .overlay-text {
                                                                                    color: var(--white);
                                                                                    padding: 10px;
                                                                                    font-size: 1rem;
                                                                                    font-variant: small-caps;
                                                                                    letter-spacing: 1px;
                                                                                    text-shadow: -1px -1px 0 #000, 1px -1px 0 #000, -1px 1px 0 #000, 1px 1px 0 #000;
                                                                                    text-align: center;
                                                                                  }
                                                                                  
                                                                                  #gallery .gallery-layout .prev-pic, #gallery .gallery-layout .next-pic {
                                                                                    display: -webkit-box;
                                                                                    display: -ms-flexbox;
                                                                                    display: flex;
                                                                                    -webkit-box-pack: center;
                                                                                        -ms-flex-pack: center;
                                                                                            justify-content: center;
                                                                                    -webkit-box-align: center;
                                                                                        -ms-flex-align: center;
                                                                                            align-items: center;
                                                                                    margin: 10px;
                                                                                  }
                                                                                  
                                                                                  #gallery .gallery-layout .prev-pic i, #gallery .gallery-layout .next-pic i {
                                                                                    display: -webkit-box;
                                                                                    display: -ms-flexbox;
                                                                                    display: flex;
                                                                                    -webkit-box-align: center;
                                                                                        -ms-flex-align: center;
                                                                                            align-items: center;
                                                                                    -webkit-box-pack: center;
                                                                                        -ms-flex-pack: center;
                                                                                            justify-content: center;
                                                                                    color: var(--dark-blue);
                                                                                    width: 100%;
                                                                                    height: 150px;
                                                                                    padding: 5px;
                                                                                  }
                                                                                  
                                                                                  #gallery .gallery-layout .prev-pic i:hover, #gallery .gallery-layout .next-pic i:hover {
                                                                                    border-radius: 5px;
                                                                                    background: var(--dark-blue);
                                                                                    color: var(--light-blue);
                                                                                    opacity: 0.7;
                                                                                    cursor: pointer;
                                                                                  }
                                                                                  
                                                                                  #gallery .gallery-layout i.dl-1 {
                                                                                    display: -webkit-box;
                                                                                    display: -ms-flexbox;
                                                                                    display: flex;
                                                                                  }
                                                                                  
                                                                                  #gallery .gallery-layout i.dl-2 {
                                                                                    display: none;
                                                                                  }
                                                                                  
                                                                                  @media screen and (max-width: 800px) {
                                                                                    #gallery .gallery-layout {
                                                                                      -webkit-box-orient: vertical;
                                                                                      -webkit-box-direction: normal;
                                                                                          -ms-flex-direction: column;
                                                                                              flex-direction: column;
                                                                                      padding: 0 20px;
                                                                                    }
                                                                                    #gallery .gallery-layout .prev-pic, #gallery .gallery-layout .next-pic {
                                                                                      width: 100%;
                                                                                      max-width: 150px;
                                                                                    }
                                                                                    #gallery .gallery-layout i.dl-1 {
                                                                                      display: none;
                                                                                    }
                                                                                    #gallery .gallery-layout i.dl-2 {
                                                                                      display: -webkit-box;
                                                                                      display: -ms-flexbox;
                                                                                      display: flex;
                                                                                      height: 100%;
                                                                                    }
                                                                                  }
                                                                                  
                                                                                  
                                                                                  
                                                                                      
                                                                                      
                                                                                      
                                                                                      
                                                                                      
                                                                                      Document
                                                                                  
                                                                                  
                                                                                  
                                                                                              
                                                                                                  navigate_beforekeyboard_arrow_up
                                                                                                  
                                                                                                      
                                                                                                      Dummy description
                                                                                                  
                                                                                                  navigate_nextkeyboard_arrow_down
                                                                                              
                                                                                          
                                                                                  
                                                                                  

                                                                                  On a real mobile device looks like this (tested with different browsers):

                                                                                  ANSWER

                                                                                  Answered 2021-Jun-09 at 12:02

                                                                                  The flex children are set to stretch by default. And when your child, that is, img tag is set to "height:auto;". It stretches.

                                                                                  You can change that behavior with "align-items" property.

                                                                                  #gallery .gallery-layout .frame {
                                                                                    display: -webkit-box;
                                                                                    display: -ms-flexbox;
                                                                                    display: flex;
                                                                                    position: relative;
                                                                                  
                                                                                    -webkit-box-align: center;
                                                                                        -ms-flex-align: center;
                                                                                            align-items: center;
                                                                                  
                                                                                  }
                                                                                  

                                                                                  Source https://stackoverflow.com/questions/67903628

                                                                                  QUESTION

                                                                                  Prepending to a Scala Iterator -- timeout?
                                                                                  Asked 2021-Jun-07 at 23:22

                                                                                  I want to prepend a new iterator to my existing iterator.

                                                                                  1. How can I prepend a new Iterator to an existing Iterator?

                                                                                  2. Why does my code cause my REPL to hang?

                                                                                  The following hangs indefinitely in my REPL:

                                                                                  scala> var i = Seq(1).iterator
                                                                                  var i: Iterator[Int] = 
                                                                                  
                                                                                  scala> i = Seq(2).iterator ++ i
                                                                                  // mutated i
                                                                                  
                                                                                  scala> i.next()
                                                                                  val res0: Int = 2
                                                                                  
                                                                                  scala> i.next()
                                                                                  . . .
                                                                                  

                                                                                  Note that the following works, but this is an append not a prepend:

                                                                                  var i = Seq(1).iterator
                                                                                  i = i ++ Seq(2).iterator
                                                                                  i.next()
                                                                                  i.next()
                                                                                  

                                                                                  This also works, but materializes the entire iterator which I cannot do:

                                                                                  var i = Seq(1).iterator
                                                                                  i = (Seq(2) ++ i.toSeq).iterator
                                                                                  i.next()
                                                                                  i.next()
                                                                                  

                                                                                  Thanks!

                                                                                  ANSWER

                                                                                  Answered 2021-Jun-07 at 23:22

                                                                                  Simply speaking, it hangs because you have there an infinite loop. In the line where you think you are merging iterators, you are actually referencing the new i (laziness) and not the initial value of i.

                                                                                  You can get over that by introducing a new var as Luis Miguel pointed out

                                                                                  var i = Seq(1).iterator
                                                                                  var j = i
                                                                                  i = Seq(2).iterator ++ j
                                                                                  i.next()
                                                                                  i.next()
                                                                                  

                                                                                  so that should do the trick. Hope it helps and is clear enough.

                                                                                  Source https://stackoverflow.com/questions/67879401

                                                                                  QUESTION

                                                                                  SICP 3.52 delayed cdr
                                                                                  Asked 2021-Jun-05 at 14:21
                                                                                  (define sum 0)
                                                                                  
                                                                                  (define (accum x)
                                                                                    (set! sum (+ x sum))
                                                                                    sum)
                                                                                  
                                                                                  ;1: (define seq (stream-map accum (stream-enumerate-interval 1 20)))
                                                                                  ;2: (define y (stream-filter even? seq))
                                                                                  ;3: (define z (stream-filter (lambda (x) (= (remainder x 5) 0))
                                                                                  ;                           seq))
                                                                                  
                                                                                  ;4: (stream-ref y 7)
                                                                                  ;5: (display-stream z)
                                                                                  

                                                                                  Step 1: ;1: ==> (cons-stream 1 (stream-map proc (stream-cdr s)) (Assume stream-cdr is evaluated only when we force the cdr of this stream)

                                                                                  sum is now 1

                                                                                  Step 2: 1 is not even, hence (also memoized so not added again), it calls (stream-filter pred (stream-cdr stream)). This leads to evaluation of cdr hence materializing 2 which is even, hence it should call: (cons-stream 2 (stream-cdr stream)).

                                                                                  According to this answer should be 1+2 = 3 , but it is 6

                                                                                  Can someone help with why the cdr's car is materialized before the current cdr is called?

                                                                                  ANSWER

                                                                                  Answered 2021-Jun-05 at 14:21
                                                                                  #lang r5rs
                                                                                  
                                                                                  (define-syntax cons-stream
                                                                                    (syntax-rules () 
                                                                                      ((_ h t) (cons h (lambda () t)))))
                                                                                  
                                                                                  (define (stream-cdr s)
                                                                                    (if (and (not (pair? (cdr s)))
                                                                                             (not (null? (cdr s))))
                                                                                        (set-cdr! s ((cdr s))))
                                                                                    (cdr s))
                                                                                  

                                                                                  we observe:

                                                                                  > sum
                                                                                  0
                                                                                  > (define seq (stream-map accum (stream-enumerate-interval 1 20)))
                                                                                  > sum
                                                                                  1
                                                                                  > seq
                                                                                  (mcons 1 #)
                                                                                  > (define y (stream-filter even? seq))
                                                                                  > sum
                                                                                  6
                                                                                  > seq
                                                                                  (mcons
                                                                                   1
                                                                                   (mcons
                                                                                    3
                                                                                    (mcons 6 #)))
                                                                                  > y
                                                                                  (mcons 6 #)
                                                                                  > 
                                                                                  

                                                                                  stream-filter? needs to get to the first element of the stream it is constructing in order to construct it. A stream has its head element already forced, calculated, so it must be already present.

                                                                                  In the list of accumulated sums of the enumerated interval from 1 to 20, the first even number is 6:

                                                                                  1      = 1
                                                                                  1+2    = 3
                                                                                  1+2+3  = 6
                                                                                  ...
                                                                                  

                                                                                  Source https://stackoverflow.com/questions/67845454

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