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List comprehension with if statement
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You got the order wrong. The if should be after the for (unless it is in an if-else ternary operator)
[y for y in a if y not in b]
This would work however:
[y if y not in b else other_value for y in a]
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How do you tell if a string contains another string in POSIX sh?
I want to write a Unix shell script that will do various logic if there is a string inside of another string. For example, if I am in a certain folder, branch off. Could someone please tell me how to accomplish this? If possible I would like to make this not shell specific (i.e. not bash only) but i...
Why '&&' and not '&'?
...at the evaluation is canceled as soon as the result is clear.
Example:
if(CanExecute() && CanSave())
{
}
If CanExecute returns false, the complete expression will be false, regardless of the return value of CanSave. Because of this, CanSave is not executed.
This is very handy in the f...
Check if the number is integer
... was surprised to learn that R doesn't come with a handy function to check if the number is integer.
12 Answers
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Shortest distance between a point and a line segment
... const float l2 = length_squared(v, w); // i.e. |w-v|^2 - avoid a sqrt
if (l2 == 0.0) return distance(p, v); // v == w case
// Consider the line extending the segment, parameterized as v + t (w - v).
// We find projection of point p onto the line.
// It falls where t = [(p-v) . (w-v)] /...
How to convert number to words in java
...= {
"",
" ten",
" twenty",
" thirty",
" forty",
" fifty",
" sixty",
" seventy",
" eighty",
" ninety"
};
private static final String[] numNames = {
"",
" one",
" two",
" three",
" four",
" five",
" six",
" seven",
" eigh...
How to get the caret column (not pixels) position in a textarea, in characters, from the start?
..., so you will have to do something like this:
function getCaret(node) {
if (node.selectionStart) {
return node.selectionStart;
} else if (!document.selection) {
return 0;
}
var c = "\001",
sel = document.selection.createRange(),
dul = sel.duplicate(),
len = 0;
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Jinja2 template variable if None Object set a default value
How to make a variable in jijna2 default to "" if object is None instead of doing something like this?
9 Answers
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Finding Number of Cores in Java
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int cores = Runtime.getRuntime().availableProcessors();
If cores is less than one, either your processor is about to die, or your JVM has a serious bug in it, or the universe is about to blow up.
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Asynchronously wait for Task to complete with timeout
I want to wait for a Task<T> to complete with some special rules:
If it hasn't completed after X milliseconds, I want to display a message to the user.
And if it hasn't completed after Y milliseconds, I want to automatically request cancellation .
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