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Grouping functions (tapply, by, aggregate) and the *apply family
Whenever I want to do something "map"py in R, I usually try to use a function in the apply family.
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Return empty cell from formula in Excel
I need to return an empty cell from an Excel formula, but it appears that Excel treats an empty string or a reference to an empty cell differently than a true empty cell. So essentially I need something like
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Creating email templates with Django
I want to send HTML-emails, using Django templates like this:
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Is passing 'this' in a method call accepted practice in java
Is it good/bad/acceptable practice to pass the current object in a method call. As in:
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How to convert enum value to int?
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You'd need to make the enum expose value somehow, e.g.
public enum Tax {
NONE(0), SALES(10), IMPORT(5);
private final int value;
private Tax(int value) {
this.value = value;
}
public int getValue() {
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Run R script from command line
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If you want the output to print to the terminal it is best to use Rscript
Rscript a.R
Note that when using R CMD BATCH a.R that instead of redirecting output to standard out and displaying on the terminal a new file called a.Rout will be created...
How to convert vector to array
How do I convert a std::vector<double> to a double array[] ?
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Using PHP with Socket.io
Is it possible to use Sockets.io on the client side and communicate with a PHP based application on the server? Does PHP even support such a 'long-lived connection' way of writing code?
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Trust Store vs Key Store - creating with keytool
I understand that the keystore would usually hold private/public keys and the trust store only public keys (and represents the list of trusted parties you intend to communicate with). Well, that's my first assumption, so if that's not correct, I probably haven't started very well...
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Remove specific commit
...unch of files that shouldn't have been edited. Somehow I merged his work into mine, either when I pulled it, or when I tried to just pick the specific files out that I wanted. I've been looking and playing for a long time, trying to figure out how to remove the commits that contain the edits to thos...