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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 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;
...
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...
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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How can I check if a key exists in a dictionary? [duplicate]
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if key in array:
# do something
Associative arrays are called dictionaries in Python and you can learn more about them in the stdtypes documentation.
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Best way to “negate” an instanceof
I was thinking if there exists a better/nicer way to negate an instanceof in Java.
Actually, I'm doing something like:
9 ...
Finding Number of Cores in Java
...
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.
share
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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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When should an IllegalArgumentException be thrown?
... 'recover' from this exception by providing an error message to the user.
If the input originates from your own system, e.g. your database, or some other parts of your application, you should be able to rely on it to be valid (it should have been validated before it got there). In this case it's pe...