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Find integer index of rows with NaN in pandas dataframe
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Here are tests for a few methods:
%timeit np.where(np.isnan(df['b']))[0]
%timeit pd.isnull(df['b']).nonzero()[0]
%timeit np.where(df['b'].isna())[0]
%timeit df.loc[pd.isna(df['b']), :].index
And their corresponding timings:
333 µ...
Understand the “Decorator Pattern” with a real world example
... OutputStream classes in java.io package
File file=new File("target","test.txt");
FileOutputStream fos=new FileOutputStream(file);
BufferedOutputStream bos=new BufferedOutputStream(fos);
ObjectOutputStream oos=new ObjectOutputStream(bos);
oos.write(5);
oos.writeBoolean(tru...
Capture HTML Canvas as gif/jpg/png/pdf?
...avigate to an image with a green square in the middle of it, but I haven't tested.
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What is the best way to concatenate two vectors?
...in turn invalidate AB.
Because every access to an element is preceded by a test (namely, "i
< v1.size()"), VecProxy access time, although constant, is also
a bit slower than that of vectors.
This approach can be generalized to n vectors. I haven't tried, but
it shouldn't be a big deal.
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Mac zip compress without __MACOSX folder?
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How might I do this recursively for all zip files?
– Wowfunhappy
Jun 27 '17 at 3:56
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How to print without newline or space?
...to the end of the string:
print('.', end='')
To not add a space between all the function arguments you want to print:
print('a', 'b', 'c', sep='')
You can pass any string to either parameter, and you can use both parameters at the same time.
If you are having trouble with buffering, you can f...
How do I filter ForeignKey choices in a Django ModelForm?
... can populate the validation data by making using the super(...).__init__ call in your overridden method. If you are making several of these queryset changes its a lot more elegant to package them by overriding the init method.
– michael
Aug 7 '09 at 4:53
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How to darken a background using CSS?
....png);
}
Reference: linear-gradient() - CSS | MDN
UPDATE: Not all browsers support RGBa, so you should have a 'fallback color'. This color will be most likely be solid (fully opaque) ex:background:rgb(96, 96, 96). Refer to this blog for RGBa browser support.
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Instance attribute attribute_name defined outside __init__
I split up my class constructor by letting it call multiple functions, like this:
6 Answers
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What is the difference between decodeURIComponent and decodeURI?
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As I had the same question, but didn't find the answer here, I made some tests in order to figure out what the difference actually is.
I did this, since I need the encoding for something, which is not URL/URI related.
encodeURIComponent("A") returns "A", it does not encode "A" to "%41"
decodeURI...