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Creating a new column based on if-elif-else condition
...df['C'] = df.apply(f, axis=1)
In [2]: df
Out[2]:
A B C
a 2 2 0
b 3 1 1
c 1 3 -1
Of course, this is not vectorized so performance may not be as good when scaled to a large number of records. Still, I think it is much more readable. Especially coming from a SAS background.
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What's a standard way to do a no-op in python?
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edited Dec 18 '09 at 3:41
answered Mar 27 '09 at 17:05
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Is an array name a pointer?
..., and you can put a value in one of them with an assignment, like this:
a[3] = 9;
Here is a pointer:
int *p;
p doesn't contain any spaces for integers, but it can point to a space for an integer. We can, for example, set it to point to one of the places in the array a, such as the first one:
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How to hide databases that I am not allowed to access
When I connect to my Heroku - Postgresql database via pgAdmin3 , It lists all the tables (about 2600). Every time I open the pgAdmin3 I have to find my own database.
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Why does this code using random strings print “hello world”?
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answered Mar 3 '13 at 4:40
FThompsonFThompson
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Select elements by attribute in CSS
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edited Mar 26 '14 at 3:22
answered Mar 16 '11 at 11:09
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jQuery hide element while preserving its space in page layout
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edited Mar 2 '12 at 3:13
Wesley Murch
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Rails mapping array of hashes onto single hash
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You could compose Enumerable#reduce and Hash#merge to accomplish what you want.
input = [{"test...
Android Studio marks R in red with error message “cannot resolve symbol R”, but build succeeds
...athaniel Ford
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answered Mar 12 '15 at 12:38
pathe.kiranpathe.kiran
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