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Is there an R function for finding the index of an element in a vector?

... @John : that's all true, but that is not what the OP asked. The OP asked, starting from a long vector, to find the first match of elements given in another one. And for completeness, I added that if you are interested in all indices, you'll...
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Python argparse ignore unrecognised arguments

Optparse, the old version just ignores all unrecognised arguments and carries on. In most situations, this isn't ideal and was changed in argparse. But there are a few situations where you want to ignore any unrecognised arguments and parse the ones you've specified. ...
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How to check if a file exists in Go?

... You could use os.IsExist() depending the case, could be more idiomatically instead of making a double negation when doing !os.IsNotExistant() – Ariel Monaco Feb 17 at 3:18 ...
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How do I log errors and warnings into a file?

How do I turn on all error and warnings and log them to a file, but to set up all of that within the script (not changing anything in php.ini)? ...
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What is the role of the bias in neural networks? [closed]

... I think that biases are almost always helpful. In effect, a bias value allows you to shift the activation function to the left or right, which may be critical for successful learning. It might help to look at a simple example. Consider this 1-input, 1-output network that has no bias: The ou...
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Container View Controller Examples [closed]

...d an example implementation would be nice. Google has turned up nothing at all. 7 Answers ...
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What is the difference between HTML tags and ?

...k element span is an inline element. This means that to use them semantically, divs should be used to wrap sections of a document, while spans should be used to wrap small portions of text, images, etc. For example: <div>This a large main division, with <span>a small bit</span>...
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Find first element in a sequence that matches a predicate

...yntax with () creates a generator, which is more efficient than generating all the list at once with []. share | improve this answer | follow | ...
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How do I use the includes method in lodash to check if an object is in the collection?

... The includes (formerly called contains and include) method compares objects by reference (or more precisely, with ===). Because the two object literals of {"b": 2} in your example represent different instances, they are not equal. Notice: ({"b": 2}...
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How do I manage MongoDB connections in a Node.js web application?

...there are multiple database.. should i open a connection for each database all together. If not, Is it OK to open and close when required? – Aman Gupta Oct 25 '16 at 14:19 ...