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In C#, should I use string.Empty or String.Empty or “” to intitialize a string?
...person - so I suggest you find out what most people on your team like, and all go with that for consistency. Personally I find "" easier to read.
The argument that "" and " " are easily mistaken for each other doesn't really wash with me. Unless you're using a proportional font (and I haven't worke...
Is generator.next() visible in Python 3?
...son for this is consistency: special methods like __init__() and __del__() all have double underscores (or "dunder" in the current vernacular), and .next() was one of the few exceptions to that rule. This was fixed in Python 3.0. [*]
But instead of calling g.__next__(), use next(g).
[*] There are ...
How to get the IP address of the docker host from inside a docker container
...r, that's what bridge IP can give you (of course in the stndard "home" installation). Why anybody would need "real" host IP if it can be even outside of docker bridge and can be unaccessible? This is the solution for all people who just installed docker and want to play with it in a short time.
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Is there a numpy builtin to reject outliers from a list
...ng like the following? That is, take a list d and return a list filtered_d with any outlying elements removed based on some assumed distribution of the points in d .
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How can I convert a string to a number in Perl?
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You don't need to convert it at all:
% perl -e 'print "5.45" + 0.1;'
5.55
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find() with nil when there are no records
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Yes, just do:
Challenge.find_by_id(10)
For Rails 4 and 5:
Challenge.find_by(id: 10)
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Composer killed while updating
I got a problem, I tried to install a new package to my Laravel 4 project.
But when I run php composer.phar update I get this:
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filter for complete cases in data.frame using dplyr (case-wise deletion)
...data.frame for complete cases using dplyr? complete.cases with a list of all variables works, of course. But that is a) verbose when there are a lot of variables and b) impossible when the variable names are not known (e.g. in a function that processes any data.frame).
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Why does SIGPIPE exist?
...zero timeout) to consume any pending SIGPIPE signal (which is sent to the calling thread, not the process) before unmasking it again.
I believe the reason SIGPIPE exists is much simpler: establishing sane default behavior for pure "filter" programs that continuously read input, transform it somehow...
Getting multiple keys of specified value of a generic Dictionary?
...e, perhaps maintain two dictionary mapping key->value and value->List_of_keys. If you do the latter you will trade storage for look up speed. It wouldn't take much to turn @Cybis example into such a data structure.
s...