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Adding new column to existing DataFrame in Python pandas
... did it wrong (it can trigger false positives) but from 0.13.0 it let you know there are more adequate methods for the same purpose. Then, if you get the warning, just follow its advise: Try using .loc[row_index,col_indexer] = value instead
>>> df1.loc[:,'f'] = pd.Series(np.random.randn(sL...
Finding the index of an item in a list
...ist in order, until it finds a match. If your list is long, and you don't know roughly where in the list it occurs, this search could become a bottleneck. In that case, you should consider a different data structure. Note that if you know roughly where to find the match, you can give index a hint. F...
How do I install cURL on cygwin?
... Install.
6) Open a cygwin window and type curl.exe (should be available now).
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Chaining multiple filter() in Django, is this a bug?
...__event=event) & Q(shiftregistrations__shifts=False)
What you can do now is to use an annotation count-filter.
In this case we count all shifts which belongs to a certain event.
qs: EventQuerySet = qs.annotate(
num_shifts=Count('shiftregistrations__shifts', filter=Q(shiftregistrations__e...
Installing Python packages from local file system folder to virtualenv with pip
...default answer. No need to make pip hunt around with --find-links if you know exactly where your package is on the local machine.
– Robert
Feb 10 at 19:33
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Make a link open a new window (not tab) [duplicate]
...is not a matter of year or browser, most modern browsers open in a new tab nowadays. You need a javascript solution like Ievgen's for this.
– Christoph
Sep 15 '15 at 14:27
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Left Align Cells in UICollectionView
... the array. You may look into the source code for its implementation.)
So now the only thing we have to do is to implement the layoutAttributesForItem(at indexPath: IndexPath) function properly. The super class UICollectionViewFlowLayout already puts the correct number of cells in each line so we o...
How to replace a hash key with another key
...er the question. The post states that the keys which need replacing are unknown... We only know that they begin with an underscore, we don't know what the keys actually are.
– Dsel
Aug 21 '15 at 6:11
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How to count the number of set bits in a 32-bit integer?
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This is known as the 'Hamming Weight', 'popcount' or 'sideways addition'.
The 'best' algorithm really depends on which CPU you are on and what your usage pattern is.
Some CPUs have a single built-in instruction to do it and others hav...
How do I time a method's execution in Java?
...ited Jul 8 '16 at 21:49
michaelsnowden
5,33022 gold badges2727 silver badges6767 bronze badges
answered Oct 7 '08 at 20:16
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