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Combine two or more columns in a dataframe into a new column with a new name

...t for example is like: A - B instead of A-B. Is it possible to remove this extra space? – Chetan Arvind Patil Oct 6 '17 at 2:35 9 ...
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What does if __name__ == “__main__”: do?

...in program, e.g. python foo.py the interpreter will assign the hard-coded string "__main__" to the __name__ variable, i.e. # It's as if the interpreter inserts this at the top # of your module when run as the main program. __name__ = "__main__" When Your Module Is Imported By Another On the other...
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Why would introducing useless MOV instructions speed up a tight loop in x86_64 assembly?

...as to rewrite the pascal FOR loop myself in assembly, at which point these extra instructions no longer had a positive effect. Perhaps free pascal's generated code was harder for the processor to predict than the simple counter I replaced it with. – tangentstorm ...
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How do I prevent site scraping? [closed]

...ometimes used for basic scraping) If you find that a specific User Agent string is used by scrapers on your site, and it is not used by real browsers or legitimate spiders, you can also add it to your blacklist. If it doesn't request assets (CSS, images), it's not a real browser. A real browser ...
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How to import CSV file data into a PostgreSQL table?

...col1': sqlalchemy.types.NUMERIC, 'col2': sqlalchemy.types.String}) #Datatypes should be [sqlalchemy types][1] share | improve this answer | follow ...
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Git and Mercurial - Compare and Contrast

...in git rev-parse manpage): The full SHA1 object name (40-byte hexadecimal string), or a substring of such that is unique within the repository A symbolic ref name, e.g. 'master' (referring to 'master' branch), or 'v1.5.0' (referring to tag), or 'origin/next' (referring to remote-tracking branch) A...
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Guaranteed lifetime of temporary in C++?

...Schaub: What is a "full-expression" in this case: printf("%s", strdup(std::string("$$$").c_str()) ); ?I mean if strdup(std::string("$$$").c_str()) is taken as the full expression, then the pointer that strdup sees is valid. If std::string("$$$").c_str() is a full expression, then the pointer that st...
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Adding two Java 8 streams, or an extra element to a stream

I can add streams or extra elements, like this: 8 Answers 8 ...
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get string value from UISegmentedControl

... Objective-C NSString *title = [segment titleForSegmentAtIndex:segment.selectedSegmentIndex]; Swift: let title = segment.titleForSegment(at: segment.selectedSegmentIndex) ...
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How to check if element exists using a lambda expression?

... } return false; } public boolean containsTabById(TabPane tabPane, String id) { return containsByLambda(tabPane.getTabs(), z -> z.getId().equals(id)); } ... if (containsTabById(tabPane, idToCheck))) { ... } ...