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What is the difference between substr and substring?
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3
@Pawel also when you want it to the end of the string (no second argument)
– André Chalella
Oct 20 '...
How to count the number of set bits in a 32-bit integer?
...ou may need to adjust it to work for a particular language (e.g. using uint32_t for C++ and >>> in Java):
int numberOfSetBits(uint32_t i)
{
// Java: use int, and use >>> instead of >>
// C or C++: use uint32_t
i = i - ((i >> 1) & 0x55555555);
i =...
Python 3: ImportError “No Module named Setuptools”
I'm having troubles with installing packages in Python 3.
9 Answers
9
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Transposing a NumPy array
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answered May 10 '11 at 18:36
Joe KingtonJoe Kington
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Create numpy matrix filled with NaNs
...ed array and assign to all entries at once:
>>> a = numpy.empty((3,3,))
>>> a[:] = numpy.nan
>>> a
array([[ NaN, NaN, NaN],
[ NaN, NaN, NaN],
[ NaN, NaN, NaN]])
I have timed the alternatives a[:] = numpy.nan here and a.fill(numpy.nan) as posted by ...
How can I access and process nested objects, arrays or JSON?
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3
Some of what's being linked here is really asking how to do this in jQuery, which to be fair does simplify 1 or 2 things here. Not sure whet...
Python list subtraction operation
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346
Use a list comprehension:
[item for item in x if item not in y]
If you want to use the - in...
Adding new column to existing DataFrame in Python pandas
... a b c d
6 -0.269221 -0.026476 0.997517 1.294385
8 0.917438 0.847941 0.034235 -0.448948
>>> df1['e'] = pd.Series(np.random.randn(sLength), index=df1.index)
>>> df1
a b c d e
6 -0.269221 -0.026476 0.997517 ...
HTML5 Canvas Resize (Downscale) Image High Quality?
...e. )
Here's an example of canvas scale vs my pixel perfect scale on a 1/3 scale of a zombat.
Notice that the picture might get scaled in your Browser, and is .jpegized by S.O..
Yet we see that there's much less noise especially in the grass behind the wombat, and the branches on its right. The n...
Sorting multiple keys with Unix sort
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Ken GentleKen Gentle
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