## Plotting graph using for loop in MATLAB

Why this happens… With plot(x(i),y) you are plotting 100 single points (one in each iteration) and they are not shown by default. Therefore the plot looks empty. Solution 1: Vectorized calculation and direct plot I assume you meant to draw a continuous line. In that case no for-loop is needed because you can calculate and … Read more

## Java for loop vs. while loop. Performance difference?

No, changing the type of loop wouldn’t matter. The only thing that can make it faster would be to have less nesting of loops, and looping over less values. The only difference between a for loop and a while loop is the syntax for defining them. There is no performance difference at all. int i … Read more

## Two semicolons inside a for-loop parentheses

for(;;) { } functionally means while (true) { } It will probably break the loop/ return from loop based on some condition inside the loop body. The reason that for(;;) loops forever is because for has three parts, each of which is optional. The first part initializes the loop; the second decides whether or not … Read more

## Which loop is faster, while or for?

That clearly depends on the particular implementation of the interpreter/compiler of the specific language. That said, theoretically, any sane implementation is likely to be able to implement one in terms of the other if it was faster so the difference should be negligible at most. Of course, I assumed while and for behave as they … Read more

## What is the meaning of list[:] in this code? [duplicate]

This is one of the gotchas! of python, that can escape beginners. The words[:] is the magic sauce here. Observe: >>> words = [‘cat’, ‘window’, ‘defenestrate’] >>> words2 = words[:] >>> words2.insert(0, ‘hello’) >>> words2 [‘hello’, ‘cat’, ‘window’, ‘defenestrate’] >>> words [‘cat’, ‘window’, ‘defenestrate’] And now without the [:]: >>> words = [‘cat’, ‘window’, ‘defenestrate’] … Read more

## Parallel Loops in C++

With the parallel algorithms in C++17 we can now use: std::vector<std::string> foo; std::for_each( std::execution::par, foo.begin(), foo.end(), [](auto&& item) { //do stuff with item }); to compute loops in parallel. The first parameter specifies the execution policy

## How do I write a ‘for’ loop in Bash?

From this site: for i in \$(seq 1 10); do echo \$i done

## Excel VBA – exit for loop

To exit your loop early you can use Exit For If [condition] Then Exit For

## Check presence of vowels in a string

vowels = {“a”, “e”, “i”, “o”, “u”, “A”, “E”, “I”, “O”, “U”} if any(char in vowels for char in word): … Note: This is better because it short circuits, as soon as it finds the vowel in the word. So, it doesn’t have to check all the characters unless there are no vowels in the … Read more

## Express for loops in swift with dynamic range

Using a helper function (originally defined at Converting a C-style for loop that uses division for the step to Swift 3) public func sequence<T>(first: T, while condition: @escaping (T)-> Bool, next: @escaping (T) -> T) -> UnfoldSequence<T, T> { let nextState = { (state: inout T) -> T? in // Return `nil` if condition is … Read more