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Pandas count(distinct) equivalent
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How to access this unique count . As there is no column nam>me m>
– Tarun Khaneja
May 3 '18 at 12:08
Thank...
Is it intended by the C++ standards committee that in C++11 unordered_map destroys what it inserts?
I've just lost three days of my life tracking down a very strange bug where unordered_map::insert() destroys the variable you insert. This highly non-obvious behaviour occurs in very recent compilers only: I found that clang 3.2-3.4 and GCC 4.8 are the only compilers to demonstrate this "feature"....
What is the equivalent of “none” in django templates?
I want to see if a field/variable is none within a Django template. What is the correct syntax for that?
7 Answers
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Does ruby have real multithreading?
...of ruby using green threads . How can I create real "OS-level" threads in my application in order to make use of multiple cpu cores for processing?
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Does a const reference class m>me m>mber prolong the life of a temporary?
...ection on initializers of reference declarations. The reference in your example is bound to the constructor's argum>me m>nt n, and becom>me m>s invalid when the object n is bound to goes out of scope.
The lifetim>me m> extension is not transitive through a function argum>me m>nt. §12.2/5 [class.temporary]:
The se...
Remove specific commit
...project, and he edited a bunch of files that shouldn't have been edited. Som>me m>how I m>me m>rged 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 tim>me m>, trying to figure out how to remove the commits that...
Why is enum class preferred over plain enum?
I heard a few people recomm>me m>nding to use enum classes in C++ because of their type safety .
9 Answers
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Locate current file in IntelliJ
...tructure? (Similar to Visual Studio's Ctrl + Alt + L ). What is the nam>me m> of the operation (so I can define it in the keymap)
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Using a constant NSString as the key for NSUserDefaults
I'm using NSUSerDefaults to store user preferences. I rem>me m>mber reading som>me m>where that setting the keys as constants is a good idea - and I agree. The following code is what I currently have:
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How do I do base64 encoding on iOS?
... 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/'
};
@implem>me m>ntation NSString (NSStringAdditions)
+ (NSString *) base64StringFromData: (NSData *)data length: (int)length {
unsigned long ixtext, lentext;
long ctremaining;
unsigned char input[3], output[4];
short i, charsonlin...