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Difference between signed / unsigned char [duplicate]
So I know that the difference between a signed int and unsigned int is that a bit is used to signify if the number if positive or negative, but how does this apply to a char ? How can a character be positive or negative?
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Why does C++ rand() seem to generate only numbers of the same order of magnitude?
In a small application written in C/C++, I am facing a problem with the rand function and maybe the seed :
9 Answers
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How can I apply a function to every row/column of a matrix in MATLAB?
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Many built-in operations like sum and prod are already able to operate across rows or columns, so you may be able to refactor the function you are applying to take advantage of this.
If that's not a viable option, one way to do it is to collect the rows or c...
How to determine equality for two JavaScript objects?
...ortant to determine whether any two instances of MyClass are equal, only a and b are important. In some cases c might vary between instances and yet not be significant during comparison.
Note this issue applies when members may themselves also be instances of a type and these each would all be req...
How do you install Google frameworks (Play, Accounts, etc.) on a Genymotion virtual device? [duplica
I'm currently trying out Genymotion and boy, it's so much faster than the ADT emulator.
10 Answers
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Can I bind an array to an IN() condition?
...right. fixed the code (didn't test it though)
edit: both chris (comments) and somebodyisintrouble suggested that the foreach-loop ...
(...)
// bindvalue is 1-indexed, so $k+1
foreach ($ids as $k => $id)
$stmt->bindValue(($k+1), $id);
$stmt->execute();
... might be redundant, so the...
Javascript calculate the day of the year (1 - 366)
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Edit: The code above will fail when now is a date in between march 26th and October 29th andnow's time is before 1AM (eg 00:59:59). This is due to the code not taking daylight savings time into account. You should compensate for this:
var now = new Date();
var start = new Date(now.getFullY...
Using getopts to process long and short command line options
I wish to have long and short forms of command line options invoked using my shell script.
32 Answers
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How to map and remove nil values in Ruby
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Ruby 2.7 is introducing filter_map for this exact purpose. It's idiomatic and performant, and I'd expect it to become the norm very soon.
For example:
numbers = [1, 2, 5, 8, 10, 13]
enum.filter_map { |i| i * 2 if i.even? }
# => [4, 16, 20]
In your case, as the block evaluates to falsey, simp...
Most efficient method to groupby on an array of objects
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Here is one that outputs array and not object: groupByArray(xs, key) { return xs.reduce(function (rv, x) { let v = key instanceof Function ? key(x) : x[key]; let el = rv.find((r) => r && r.key === v); ...