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data.table vs dplyr: can one do something well the other can't or does poorly?
...j and by together is by design. By keeping related operations together, it allows to easily optimise operations for speed and more importantly memory usage, and also provide some powerful features, all while maintaining the consistency in syntax.
1. Speed
Quite a few benchmarks (though mostly on g...
What's the absurd function in Data.Void useful for?
... f -> onAwait $ \x -> foldConsumer onPure onAwait (f x)
Yield x _ -> absurd x
or alternatively, that you can ignore the yield case when dealing with consumers. This is the general version of this design pattern: use polymorphic data types and Void to get rid of possibilities when yo...
Modulo operation with negative numbers
...
C99 requires that when a/b is representable:
(a/b) * b + a%b shall equal a
This makes sense, logically. Right?
Let's see what this leads to:
Example A. 5/(-3) is -1
=> (-1) * (-3) + 5%(-3) = 5
This can only happen if 5%(-3) is 2.
Example B. (-5)/3 is -1
=> (-1) * 3 + (-5...
Access Denied for User 'root'@'localhost' (using password: YES) - No Privileges?
...ost, User, Password) VALUES ('%', 'root', password('YOURPASSWORD'));
GRANT ALL ON *.* TO 'root'@'%' WITH GRANT OPTION;
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Is there a way to make a PowerShell script work by double clicking a .ps1 file?
... @UjjwalSingh: -NoProfile is also helpful, since the profile can do all kinds of things that the script doesn't expect.
– Joey
Apr 3 '17 at 6:28
6
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jQuery Validate - Enable validation for hidden fields
...ry, this could break an existing
setup. In the unlikely case that it actually does, you can fix it by
setting the ignore-option to “[]” (square brackets without the
quotes)."
To change this setting for all forms:
$.validator.setDefaults({
ignore: [],
// any other default option...
How to convert wstring into string?
...e <locale>
#include <vector>
int main() {
std::setlocale(LC_ALL, "");
const std::wstring ws = L"ħëłlö";
const std::locale locale("");
typedef std::codecvt<wchar_t, char, std::mbstate_t> converter_type;
const converter_type& converter = std::use_facet<converter...
The performance impact of using instanceof in Java
...y heavy use of the instanceof operator. While I know that OO design generally tries to avoid using instanceof , that is a different story and this question is purely related to performance. I was wondering if there is any performance impact? Is is just as fast as == ?
...
How to do case insensitive string comparison?
...y to do it (if you're not worried about special Unicode characters) is to call toUpperCase:
var areEqual = string1.toUpperCase() === string2.toUpperCase();
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Failed to Attach to Process ID Xcode
...-> In the each simulator version of iOS -> Applications -> Delete all the files present here.
Now go to Products -> Clean
Now run it on any simulator and it will work.
Method 2 :
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