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Creating a zero-filled pandas data frame
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140
You can try this:
d = pd.DataFrame(0, index=np.arange(len(data)), columns=feature_list)
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Determine a string's encoding in C#
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answered Feb 6 '10 at 17:31
devdimidevdimi
2,3561818 silver badges1717 bronze badges
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How can I apply a function to every row/column of a matrix in MATLAB?
...m the columns of a matrix M. You can do this simply using sum:
M = magic(10); %# A 10-by-10 matrix
columnSums = sum(M, 1); %# A 1-by-10 vector of sums for each column
And here is how you would do this using the more complicated num2cell/cellfun option:
M = magic(10); ...
How do Python's any and all functions work?
...or example,
>>> multiples_of_6 = (not (i % 6) for i in range(1, 10))
>>> any(multiples_of_6)
True
>>> list(multiples_of_6)
[False, False, False]
Here, (not (i % 6) for i in range(1, 10)) is a generator expression which returns True if the current number within 1 and 9 i...
How to change plot background color?
...an use set_facecolor:
ax.set_facecolor('xkcd:salmon')
ax.set_facecolor((1.0, 0.47, 0.42))
As a refresher for what colors can be:
matplotlib.colors
Matplotlib recognizes the following formats to specify a color:
an RGB or RGBA tuple of float values in [0, 1] (e.g., (0.1, 0.2, 0....
Appropriate datatype for holding percent values?
What is the best datatype for holding percent values ranging from 0.00% to 100.00%?
5 Answers
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Why is early return slower than else?
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+100
This is a pure guess, and I haven't figured out an easy way to check whether it is right, but I have a theory for you.
I tried your ...
Pandas every nth row
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207
I'd use iloc, which takes a row/column slice, both based on integer position and following norm...
Any shortcut to initialize all array elements to zero?
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A default value of 0 for arrays of integral types is guaranteed by the language spec:
Each class variable, instance variable, or array component is initialized with a default value when it is created (§15.9, §15.10) [...] For type int, th...