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Learning Regular Expressions [closed]
...stand how the building blocks work, differences in syntax amount to little more than mild dialects. A layer on top of your regular expression engine's syntax is the syntax of the programming language you're using. Languages such as Perl remove most of this complication, but you'll have to keep in mi...
How do I check if a string is a number (float)?
... don't think that the code is perfect (but I think it's very close): it is more usual to put only the part being "tested" in the try clause, so I would put the return True in an else clause of the try. One of the reasons is that with the code in the question, if I had to review it, I would have to ...
In STL maps, is it better to use map::insert than []?
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I updated to be more clear that map::insert never replaces. I left the else because I think using value is clearer than than the iterator. Only if the value's type had an unusual copy ctor or op== would it be different, and that type would...
Correct way to use StringBuilder in SQL
... Will that take memory equal to using String like below?
No, it'll cause more memory churn than just the straight concat you quoted. (Until/unless the JVM optimizer sees that the explicit StringBuilder in the code is unnecessary and optimizes it out, if it can.)
If the author of that code wants t...
What is the difference between background and background-color
...background-color, using the background shorthand you could also add one or more values without repeating any other background-* property more than once.
Which one to choose is essentially up to you, but it could also depend on specific conditions of your style declarations (e.g if you need to overr...
How can I initialise a static Map?
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Haskell, Lisp, and verbosity [closed]
...-order function (and I include monads, arrows, etc.), but it might require more thinking (but only the first time, and it's fun and you'll be a better programmer for it), and
the static system is sufficiently general that it never gets in your way, and somewhat surprisingly it actually "aids in achi...
Extracting extension from filename in Python
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wouldn't endswith() not be more portable and pythonic?
– Sebastian Mach
Aug 28 '13 at 16:42
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Is there a valid reason for enforcing a maximum width of 80 characters in a code file, this day and
...mewhat depending on other parameters) because longer lines do make reading more difficult. Maximum code line length could be argued, but 80 is convenient for historical and practical reasons.
– Steve S
Jan 26 '09 at 16:53
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Pretty-print an entire Pandas Series / DataFrame
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You can also use the option_context, with one or more options:
with pd.option_context('display.max_rows', None, 'display.max_columns', None): # more options can be specified also
print(df)
This will automatically return the options to their previous values.
If you ...