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Is there an R function for finding the index of an element in a vector?
In R, I have an element x and a vector v . I want to find the first index of an element in v that is equal to x . I know that one way to do this is: which(x == v)[[1]] , but that seems excessively inefficient. Is there a more direct way to do it?
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Why main does not return 0 here?
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That rule was added in the 1999 version of the C standard. In C90, the status returned is undefined.
You can enable it by passing -std=c99 to gcc.
As a side note, interestingly 9 is returned because it's the return of printf which just wrote 9 characters.
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jQuery: Test if checkbox is NOT checked
...res the actual state of the checkbox. If you wish you can inspect the page and try to check and uncheck a checkbox, and you will notice the attribute "checked" (if present) will remain the same. This attribute only represents the initial state of the checkbox, and not the current state. The current ...
public friend swap member function
In the beautiful answer to the copy-and-swap-idiom there is a piece of code I need a bit of help:
2 Answers
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target=“_blank” vs. target=“_new”
What's the difference between <a target="_new"> and <a target="_blank"> and which should I use if I just want to open a link in a new tab/window?
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Utils to read resource text file to String (Java) [closed]
... Resources.getResource("foo.txt");
String text = Resources.toString(url, StandardCharsets.UTF_8);
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GOBIN not set: cannot run go install
...(where 'DIR' is a GOPATH folder):
The bin directory holds compiled commands.
Each command is named for its source directory, but only the final element, not the entire path. That is, the command with source in DIR/src/foo/quux is installed into DIR/bin/quux, not DIR/bin/foo/quux. The "foo/" pr...
Why is there huge performance hit in 2048x2048 versus 2047x2047 array multiplication?
...L is always power of 2.
The six comes from fact that 2^6 == 64 bytes is standard size of cache line.
Now what does this mean? Well it means that if I have address X and address Y and
(X >> 6) - (Y >> 6) is divisible by L (i.e. some large power of 2), they will be stored in the same ca...
Is there something like RStudio for Python? [closed]
In RStudio, you can run parts of code in the code editing window, and the results appear in the console.
10 Answers
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Passing Data between View Controllers
I'm new to iOS and Objective-C and the whole MVC paradigm and I'm stuck with the following:
46 Answers
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