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How to run code when a class is subclassed? [duplicate]
...- Watcher subclasses type, not object. 2 - SuperClass has no superclass at all, not object. I'm just so used to writing down object as a superclass for every class I defined that I somehow missed it that this code was using something else. Although there doesn't seem to be any harm in making SuperCl...
How to keep environment variables when using sudo
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To allow -E (preserve environment) for wget, you need to specify the SETENV tag on the sudo rule that allows the running of wget -- Example: <username> ALL=(root) NOPASSWD:SETENV: <path to wget>
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What are the “standard unambiguous date” formats for string-to-date conversion in R?
...te (+1). However, the error message "standard unambiguous format" is ironically ambiguous, to which the 23 previous questions attest. A more direct error message like, "format not recognized, see documentation" might improve user experience. Also, I don't believe "01/01/2000" is ISO-8601 ("2000-01-0...
Is there a standard sign function (signum, sgn) in C/C++?
...T val) {
return (T(0) < val) - (val < T(0));
}
Benefits:
Actually implements signum (-1, 0, or 1). Implementations here using copysign only return -1 or 1, which is not signum. Also, some implementations here are returning a float (or T) rather than an int, which seems wasteful.
Works ...
How to find out if an installed Eclipse is 32 or 64 bit version?
...e the line with text:
plugins/org.eclipse.equinox.launcher.win32.win32.x86_64_1.0.200.v20090519
then it is 64 bit.
If it would be plugins/org.eclipse.equinox.launcher.win32.win32.x86_32_1.0.200.v20090519 then it is 32 bit.
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Saving images in Python at a very high quality
...nd trying to get good figures in a latex document, save as an eps. Specifically, try something like this after running the commands to plot the image:
plt.savefig('destination_path.eps', format='eps')
I have found that eps files work best and the dpi parameter is what really makes them look good ...
What does `someObject.new` do in Java?
... And, as you can tell, this can be incredibly confusing. Ideally, inner classes should be implementation details of the outer class and not be exposed to the outside world.
– Eric Jablow
Mar 30 '13 at 23:45
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How to detect if a script is being sourced
I have a script where I do not want it to call exit if it's being sourced.
17 Answers
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Replacing some characters in a string with another character
I have a string like AxxBCyyyDEFzzLMN and I want to replace all the occurrences of x , y , and z with _ .
5 Answers
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When would anyone use a union? Is it a remnant from the C-only days?
I have learned but don't really get unions. Every C or C++ text I go through introduces them (sometimes in passing), but they tend to give very few practical examples of why or where to use them. When would unions be useful in a modern (or even legacy) case? My only two guesses would be programming ...