can-ajax | Ajax can.Component - Ajax
kandi X-RAY | can-ajax Summary
kandi X-RAY | can-ajax Summary
Ajax can.Component
Support
Quality
Security
License
Reuse
Top functions reviewed by kandi - BETA
Currently covering the most popular Java, JavaScript and Python libraries. See a Sample of can-ajax
can-ajax Key Features
can-ajax Examples and Code Snippets
Community Discussions
Trending Discussions on Programming Style
QUESTION
What programming style should I use?
...ANSWER
Answered 2022-Mar-01 at 21:31It depends.
There is an old rule "three or more, use for
". (source)
On the other hand, sometimes unrolling a loop can offer a speed-up. (But that's generally more true in C or assembly.)
You should do what makes your program more clear.
For example, in the code below, I wrote out the calculations for the ABD matrix of a fiber reinforced composite laminate, because making nested loops would make it more complex in this case;
QUESTION
/**
* Checks if the given index is in range. If not, throws an appropriate
* runtime exception. This method does *not* check if the index is
* negative: It is always used immediately prior to an array access,
* which throws an ArrayIndexOutOfBoundsException if index is negative.
*/
private void rangeCheck(int index) {
if (index >= size)
throw new IndexOutOfBoundsException(outOfBoundsMsg(index));
}
...ANSWER
Answered 2022-Feb-28 at 14:23It's a micro-optimization. For code clarity you might prefer the same exception for both, but when you're in a hot loop you'll want to avoid an unnecessary operation. ArrayList
being an old class, the effect this has may have varied between times and JDK versions. If someone has enough interest they could benchmark it with 1.8 and newer JDKs to see how much of an optimization it is for get()
.
Since accessing a negative array index will fail anyway, there is no need to check for it. However the size of the ArrayList
is not always the same as the size of its internal array, so it needs to be checked explicitly.
As to why rangeCheckForAdd
does check for negative indexes, good question. Adding is slow anyway, so the micro-optimization wouldn't make much of a difference. Maybe they wanted consistent error messaging here.
QUESTION
I am using a functional programming style to solve the Leetcode easy question, Count the Number of Consistent Strings. The premise of this question is simple: count the amount of values for which the predicate of "all values are in another set" holds.
I have two approaches, one which I am fairly certain behaves as I want it to, and the other which I am less sure about. Both produce the correct output, but ideally they would stop evaluating other elements after the output is in a final state.
...ANSWER
Answered 2022-Jan-12 at 09:30The actual term you’re asking for is short-circuiting
Further, some operations are deemed short-circuiting operations. An intermediate operation is short-circuiting if, when presented with infinite input, it may produce a finite stream as a result. A terminal operation is short-circuiting if, when presented with infinite input, it may terminate in finite time. Having a short-circuiting operation in the pipeline is a necessary, but not sufficient, condition for the processing of an infinite stream to terminate normally in finite time.
The term “lazy” only applies to intermediate operations and means that they only perform work when being requested by the terminal operation. This is always the case, so when you don’t chain a terminal operation, no intermediate operation will ever process any element.
Finding out whether a terminal operation is short-circuiting, is rather easy. Go to the Stream
API documentation and check whether the particular terminal operation’s documentation contains the sentence
This is a short-circuiting terminal operation.
allMatch
has it, reduce
has not.
This does not mean that such optimizations based on logic or algebra are impossible. But the responsibility lies at the JVM’s optimizer which might do the same for loops. However, this requires inlining of all involved methods to be sure that this conditions always applies and there are no side effect which must be retained. This behavioral compatibility implies that even if the processing gets optimized away, a peek(System.out::println)
would keep printing all elements as if they were processed. In practice, you should not expect such optimizations, as the Stream implementation code is too complex for the optimizer.
QUESTION
I am using a functional programming style to solve the Leetcode easy question, Count the Number of Consistent Strings. The premise of this question is simple: count the amount of values for which the predicate of "all values are in another set" holds.
I was able to do this pretty concisely like so:
...ANSWER
Answered 2022-Jan-12 at 00:03The docs don't explicitly say, but this is easy enough to test.
QUESTION
I implemented the following code to calculate weighted avg with for loops, how can I be more func programming style and use map
and zip
?
ANSWER
Answered 2021-Oct-19 at 00:00Here is one way, although I'm not sure if it's the most elegant
QUESTION
I have searched on this site the topics about malloc
on structs. However, I have a slightly problem. Is that malloc
on the element of a struct different from malloc
on the whole struct, especially when that struct is quite simple, that is, only a member that is exactly what we all want to allocate? To be clear, see the code corresponding to student
and student2
structs below.
ANSWER
Answered 2021-Sep-23 at 16:15First, you dynamically allocate one struct, but not the other. So you're comparing apples to oranges.
Statically-allocated structs:
QUESTION
I'm currently reading this book called CLRS 2.2 page 25. In which the author describes the Running time of an algorithm as
The running time of an algorithm on a particular input is the number of primitive operations or “steps” executed.
Also the author uses the running time to analyze algorithms. Then I referred a book called Data Structures and Algorithms made easy by Narasimha Karumanchi. In which he describes the following.
1.7 Goal of the Analysis of Algorithms The goal of the analysis of algorithms is to compare algorithms (or solutions) mainly in terms of running time but also in terms of other factors (e.g., memory, developer effort, etc.)
1.9 How to Compare Algorithms: To compare algorithms, let us define a few objective measures:
Execution times? Not a good measure as execution times are specific to a particular computer.
Number of statements executed? Not a good measure, since the number of statements varies with the programming language as well as the style of the individual programmer.
Ideal solution? Let us assume that we express the running time of a given algorithm as a function of the input size n (i.e., f(n)) and compare these different functions corresponding to running times. This kind of comparison is independent of machine time, programming style, etc.
As you can see from CLRS the author describes the running time as the number of steps executed whereas in the second book the author says its not a good measure to use Number of step executed to analyze the algorithms. Also the running time depends on the computer (my assumption) but the author from the second book says that we cannot consider the Execution time to analyze algorithms as it totally depends on the computer.
I thought the execution time and the running time are same!
So,
- What is the real meaning or definition of running time and execution time? Are they the same of different?
- Does running time describe the number of steps executed or not?
- Does running time depend on the computer or not?
thanks in advance.
...ANSWER
Answered 2021-Aug-08 at 07:57What is the real meaning or definition of running time and execution time? Are they the same of different?
The definition of "running time" in 'Introduction to Algorithms' by C,L,R,S [CLRS] is actually not a time, but a number of steps. This is not what you would intuitively use as a definition. Most would agree that "runnning" and "executing" are the same concept, and that "time" is expressed in a unit of time (like milliseconds). So while we would normally consider these two terms to have the same meaning, in CLRS they have deviated from that, and gave a different meaning to "running time".
Does running time describe the number of steps executed or not?
It does mean that in CLRS. But the definition that CLRS uses for "running time" is particular, and not the same as you might encounter in other resources.
CLRS assumes here that a primitive operation (i.e. a step) takes O(1) time.
This is typically true for CPU instructions, which take up to a fixed maximum number of cycles (where each cycle represents a unit of time), but it may not be true in higher level languages. For instance, some languages have a sort
instruction. Counting that as a single "step" would give useless results in an analysis.
Breaking down an algorithm into its O(1) steps does help to analyse the complexity of an algorithm. Counting the steps for different inputs may only give a hint about the complexity though. Ultimately, the complexity of an algorithm requires a (mathematical) proof, based on the loops and the known complexity of the steps used in an algorithm.
Does running time depend on the computer or not?
Certainly the execution time may differ. This is one of the reasons we want to by a new computer once in a while.
The number of steps may depend on the computer. If both support the same programming language, and you count steps in that language, then: yes. But if you would do the counting more thoroughly and would count the CPU instructions that are actually ran by the compiled program, then it might be different. For instance, a C compiler on one computer may generate different machine code than a different C compiler on another computer, and so the number of CPU instructions may be less on the one than the other, even though they result from the same C program code.
Practically however, this counting at CPU instruction level is not relevant for determining the complexity of an algorithm. We generally know the time complexity of each instruction in the higher level language, and that is what counts for determining the overall complexity of an algorithm.
QUESTION
Some Background (feel free to skip):
I'm very new to Rust, I come from a Haskell background (just in case that gives you an idea of any misconceptions I might have).
I am trying to write a program which, given a bunch of inputs from a database, can create customisable reports. To do this I wanted to create a Field
datatype which is composable in a sort of DSL style. In Haskell my intuition would be to make Field
an instance of Functor
and Applicative
so that writing things like this would be possible:
ANSWER
Answered 2021-Jun-10 at 12:54So I seem to have fixed it, although I'm still not sure I understand exactly what I've done...
QUESTION
I am trying to learn Common Lisp with the book Common Lisp: A gentle introduction to Symbolic Computation. In addition, I am using SBCL, Emacs and Slime.
In chapter 7, the author suggests there are three styles of programming the book will cover: recursion, iteration and applicative programming.
I am interested on the last one. This style is famous for the applicative operator funcall
which is the primitive responsible for other applicative operators such as mapcar
.
Thus, with an educational purpose, I decided to implement my own version of mapcar
using funcall
:
ANSWER
Answered 2021-May-21 at 17:36QUESTION
I am trying use object oriented programming style to write the code for a Tkinter app. I want to use a class method to place labels(or other widgets) to the GUI. The code I wrote is adding a character which I don't expect to the GUI. How can I write the initial add_label method so that it does not add the unwanted character. Below is my code and a screenshot. I am new to OOP, so i might be missing something.
...ANSWER
Answered 2021-May-07 at 09:22What do you expect self.add_label(root)
to do? According to your method definition, it takes text
as argument, so when you say self.add_label(root)
, you are passing root
as text
. And what is root
? It is '.'
, so remove it and it'll be gone.
Though a proper way to do this will be to pass a parent
argument to the method and use that while widget creation:
And the important part is, your instantiating the class
wrong. Keep a reference to it, rather than creating a lot of instances.
Community Discussions, Code Snippets contain sources that include Stack Exchange Network
Vulnerabilities
No vulnerabilities reported
Install can-ajax
Support
Reuse Trending Solutions
Find, review, and download reusable Libraries, Code Snippets, Cloud APIs from over 650 million Knowledge Items
Find more librariesStay Updated
Subscribe to our newsletter for trending solutions and developer bootcamps
Share this Page