pcell | pcells for various magnetic passive devices | Change Data Capture library

I'm pretty new so apologies if my title doesn't phrase things correctly. I've been hacking away and haven't been able to find an answer to this problem.

I have a horizontally scrolling collection. I'm trying to visually show poll results programatically adding CGRect to the relevant item in the collection based on voting data held in a Firestore array.

This is working, but the problem is when you scroll away (so the item in the collection is off screen) and then back, the code to draw the CGRects gets triggered again and more graphics get added to the view. Is there a way to delete these CGRects when the user scrolls an item collection off screen so when the user scrolls the item back into view, code is triggered again it doesn't create duplicates?

Here are a couple of screenshots showing first and second load

Here is my code (cell b is where the CGrect gets triggered)

I'm trying to implement an A* algorithm for pathfinding in my 3D grid. I've been following a tutorial but I'm not getting a valid path. I've stepped through my code to find out what's going on, but I don't know how to solve the problem. For the most basic test I'm just using a 2-D grid (it's 3-D, but there's only one Z option, so basically 2-D).

Here's what it's doing:

So we start at 0,0 (orange) and want to get to 1,2 (green). First it calculates the two options for the orange square, north and east, and gets distances of 2 and 1.414 for F values of 3 and 2.414. It moves to the east square (0,1). Great. But now it calculates the two open squares from 0,1 which are 1,1 and 0,2, both of which have a g value of 2 and an h value (distance) of 1, making their F values both be 3.

Since their F values are 3 and we already have an option with an F value of 3 (1,0 from the starting point), these two options are ignored even though they are clearly the best options.

It then continues onward and switches to moving to 1,0 where it then calculates 1,1 as 3 again and 2,0 as 4.236. 1,1's f value is not bigger than our current f value though, so it's ignored and we move upward to 2,0.

2,0 can only move right so it does.

2,1 can only move down since 2,2 is an invalid square, but the f value of moving to 1,1 is saved as 3, so it's again ignored, leaving us with no valid path between 0,0 and 1,2. What am I missing?

Here's a snippet of my path loop. There's a bunch of custom structs in here, and I'm using TMap from Unreal Engine to store my closed list, but I don't think that matters to the question. Here's a quick and dirty about what these structs are:

• PCell: Holds cell coordinates
• PPair: Holds cell coordinates as a PCell and an F value
• FVectorInt: 3-D integer vector
• FPathCell: Holds parent coordinates, and f, g, and h values.
• cellDetails is a 3D dynamic array of FPathCell
• closedMap is a TMap with as

Also locationIsWalkable(FVectorInt, StepDirection) is just code that checks to see if the player can walk to a cell from a certain direction. You can ignore that part.

Can anyone explain the meaning of the code and give an example how to use it? I can understand foo[100], but not bar.

I want to convert a logistic model built by the mlr-package directly into a XML-file using the package pmml. The problem is that the model.learner built by the mlr wrapper doesn't include the model link in the list, like it is in the normal stats::glm function. So here is an example:

I have read here that the way to fetch multiple entities with 1 NSFetchedResultsController is to use a parent child inheritance model. I have such a model:

https://imgur.com/a/nckHzvr

As you can see, TextPost,VideoPost, and ImagePost all have Skill as a parent entity. I am trying to make a single collectionView for which all three children show up. I am a little confused as to how to set the delegate methods though...

Here is the code for the view controller