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Regex how to match an optional character
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256
Use
[A-Z]?
to make the letter optional. {1} is redundant. (Of course you could also write [A...
How to return a part of an array in Ruby?
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195
Yes, Ruby has very similar array-slicing syntax to Python. Here is the ri documentation for the ...
How to make good reproducible pandas examples
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5 Answers
5
Active
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Fast permutation -> number -> permutation mapping algorithms
I have n elements. For the sake of an example, let's say, 7 elements, 1234567. I know there are 7! = 5040 permutations possible of these 7 elements.
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Regex to remove all (non numeric OR period)
I need for text like "joe ($3,004.50)" to be filtered down to 3004.50 but am terrible at regex and can't find a suitable solution. So only numbers and periods should stay - everything else filtered. I use C# and VS.net 2008 framework 3.5
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What is :: (double colon) in Python when subscripting sequences?
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257
it means 'nothing for the first argument, nothing for the second, and jump by three'. It gets e...
Crontab Day of the Week syntax
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385
0 and 7 both stand for Sunday, you can use the one you want, so writing 0-6 or 1-7 has the same ...
How to apply a function to two columns of Pandas dataframe
...n [49]: df
Out[49]:
0 1
0 1.000000 0.000000
1 -0.494375 0.570994
2 1.000000 0.000000
3 1.876360 -0.229738
4 1.000000 0.000000
In [50]: def f(x):
....: return x[0] + x[1]
....:
In [51]: df.apply(f, axis=1) #passes a Series object, row-wise
Out[51]:
0 1....