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How to check if a column exists in Pandas
...'A', df['B']) + df['C']
The DataFrame get method has similar behavior as python dictionaries.
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Getting “Lock wait timeout exceeded; try restarting transaction” even though I'm not using a transac
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For those using Python MySQL Connector use connection.commit() to commit the INSERT or UPDATE you've just shot through.
– AER
Sep 12 '19 at 7:00
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Require either of two arguments using argparse
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I never would have guessed it was so easy! Love you Python 3.6!
– bjd2385
Apr 30 '17 at 5:09
Wh...
Why are regular expressions so controversial? [closed]
...t's why you have to carefully tune your regular expressions in Perl, Java, Python, Ruby… Old-style regular expression engines (in grep, for example) first compile the pattern to a DFA. Afterwards, the complexity of the pattern is largely irrelevant. I just used Java and grep for the same text and ...
How do I get whole and fractional parts from double in JSP/Java?
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The confusion here is because some languages, such as Python, use % to mean modulo (-3.25 % 1 == 0.75) and others, such as Java, Fortran, C, and C++, use % to mean remainder (-3.25 % 1 == -0.25). WindRider may have typed it into a Python REPL for expediency, but that answer is ...
What's the difference between passing by reference vs. passing by value?
... CLU in 1975 and has since been adopted by many other languages, including Python and Ruby. And many more languages use a hybrid approach, where some types are "value types" and others are "reference types" -- among them are C#, Java, and JavaScript.
4There's nothing bad with recycling a fitting ol...
How can I use a C++ library from node.js?
...7/2019 compile issues with node-ffi. It's a major PITA! Is it dependent on Python 2.7 or is that just the build process? There must be a LoadLibrary mechanism in NodeJS for a standard Win32 DLL?
– tgraupmann
Oct 30 '19 at 20:48
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Learning Regular Expressions [closed]
...ar Expressions Online Tester
Regex Buddy
Regex 101 (for PCRE, JavaScript, Python, Golang)
Visual RegExp
Expresso (for .NET)
Rubular (for Ruby)
Regular Expression Library (Predefined Regexes for common scenarios)
Txt2RE
Regex Tester (for JavaScript)
Regex Storm (for .NET)
Debuggex (visual regex test...
How can I get all the request headers in Django?
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According to the documentation request.META is a "standard Python dictionary containing all available HTTP headers". If you want to get all the headers you can simply iterate through the dictionary.
Which part of your code to do this depends on your exact requirement. Anyplace that...
Sorting object property by values
...and the latter does the whole object into an array of [key, value] arrays; Python's equivalent of dict.values() and dict.items().
The features make it pretty easier to sort any hash into an ordered object. As of now, only a small portion of JavaScript platforms support them, but you can try it on Fi...