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What is the most efficient way to loop through dataframes with pandas? [duplicate]

...on to use numpy functions to avoid iterating over rows will produce the fastest code. share | improve this answer | follow | ...
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Get fragment (value after hash '#') from a URL in php [closed]

... Did you test this? Does it work? Others are saying the anchor name is never sent in the request. – David Spector Jan 2 at 17:03 ...
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How do I get class name in PHP?

...nClass is a pretty productive option. class MyClass { public function test() { // 'MyClass' return (new \ReflectionClass($this))->getShortName(); } } Benchmark: Method Name Iterations Average Time Ops/second -------------- ------------ -------------- ...
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What is the performance cost of having a virtual method in a C++ class?

...ory. This is always a significant stall: on Xenon, about 650 cycles (by my tests). However this isn't a problem specific to virtual functions because even a direct function call will cause a miss if you jump to instructions that aren't in cache. What matters is whether the function has been run be...
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Get difference between 2 dates in JavaScript? [duplicate]

...(), b.getDate()); return Math.floor((utc2 - utc1) / _MS_PER_DAY); } // test it const a = new Date("2017-01-01"), b = new Date("2017-07-25"), difference = dateDiffInDays(a, b); This works because UTC time never observes DST. See Does UTC observe daylight saving time? p.s. After discuss...
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Python's json module, converts int dictionary keys to strings

... isinstance(v, unicode) else v) for k,v in x.items()} return x Which tests the instance of the values and casts them only if they are strings objects (unicode to be exact). Both functions assumes keys (and values) to be integers. Thanks to: How to use if/else in a dictionary comprehension?...
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Does Git warn me if a shorthand commit ID can refer to 2 different commits?

... 'git <command> [<revision>...] -- [<file>...]' I just tested this on a real Git repository, by finding commits with duplicate prefixes like this: git rev-list master | cut -c-4 | sort | uniq -c | sort -nr | head This takes the list of revisions in master, cuts out the first 4...
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Match everything except for specified strings

...x library and it only works like this : ^(?!red|green|blue). Also true for testing it on regex101.com . So is the above a typo missing a ^ or does it actually work like that in Java/Perl/Python .. ? – Peter Jul 31 '19 at 9:47 ...
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byte[] to hex string [duplicate]

... of each of the methods listed here for the hell of it. I based the speed testing code off this. The result is that BitConverter+String.Replace seems to be faster than most other simple ways. But the speed can be improved with algorithms like Nathan Moinvaziri's ByteArrayToHexString or Kurt's ToH...
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How to convert std::string to lower case?

...:locale, std::tolower int main () { std::locale loc; std::string str="Test String.\n"; for(auto elem : str) std::cout << std::tolower(elem,loc); } share | improve this answer ...