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To find whether a column exists in data frame or not
...and that your column name to check is "d", you can use the %in% operator:
if("d" %in% colnames(dat))
{
cat("Yep, it's in there!\n");
}
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follo...
Erasing elements from a vector
...in), vec.end());
What happens is that remove compacts the elements that differ from the value to be removed (number_in) in the beginning of the vector and returns the iterator to the first element after that range. Then erase removes these elements (whose value is unspecified).
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How do I break out of nested loops in Java?
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Like other answerers, I'd definitely prefer to put the loops in a different method, at which point you can just return to stop iterating completely. This answer just shows how the requirements in the question can be met.
You can use break with a label for the outer loop. For example:
publi...
How to atomically delete keys matching a pattern using Redis
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Important note: this fails if you have more than a couple thousand keys matching the prefix.
– Nathan Osman
Aug 8 '14 at 16:42
93
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How do you run multiple programs in parallel from a bash script?
...t tried this, and it didn't work as expected for me. However, a slight modification worked: prog1 & prog2 ; fg This was for running multiple ssh tunnels at once. Hope this helps someone.
– jnadro52
Jan 20 '16 at 20:18
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Remove Last Comma from a string
Using JavaScript, how can I remove the last comma, but only if the comma is the last character or if there is only white space after the comma? This is my code.
I got a working fiddle . But it has a bug.
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How exactly does the “Specific Version” property of an assembly reference work in Visual Studio?
Today I had a closer look at the "Specific Version" property of assembly references in Visual Studio 2010. After a few experiments with unexpected results I set out to learn as much as possible about how the property works. Even SO, it appears to me, does not have all the answers, so here is my atte...
Delete directory with files in it?
...n!). Here is an example:
public static function deleteDir($dirPath) {
if (! is_dir($dirPath)) {
throw new InvalidArgumentException("$dirPath must be a directory");
}
if (substr($dirPath, strlen($dirPath) - 1, 1) != '/') {
$dirPath .= '/';
}
$files = glob($dirPath...
jquery selector for id starts with specific text [duplicate]
...of the divs & use
$('.commonClass').
But you can use the first one if html markup is not in your hands & cannot change it for some reason.
Alternative solution - 2 (not recommended if n is a large number)
(as per @Mihai Stancu's suggestion)
$('#editDialog-0, #editDialog-1, #editDialog-...
How to read from stdin line by line in Node
...
I think you can just change process.stdout to a different writable stream — it could be as simple as output: new require('stream').Writable()
– Jeff Sisson
Nov 20 '13 at 4:45
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