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Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
... (n > 0).
These new columns result from the application of a function to one of the columns in the dataframe.
2 Answers
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How does zip(*[iter(s)]*n) work in Python?
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FWIW, you can get the same result with map() with an initial argument of None:
>>> map(None,*[iter(s)]*3)
[(1, 2, 3), (4, 5, 6), (7, 8, 9)]
For more on zip() and map(): http://muffinresearch.co.uk/archives/2007/10/16/python-transposing-lists-with-map-and-zip/
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How can I obtain the element-wise logical NOT of a pandas Series?
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Wierd, I actually tested the tilde as it was mentioned in the documentation, but it didn't perform the same as np.invert :S
– root
Apr 14 '13 at 13:11
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How to use > in an xargs command?
...never use xargs without the -0 option (unless for very rare and controlled one-time interactive use where you aren't worried about destroying your data).
Also don't parse ls. Ever. Use globbing or find instead: http://mywiki.wooledge.org/ParsingLs
Use find for everything that needs recursion and...
If vs. Switch Speed
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So a conclusion might be use switch/case for simple types that are only one level deep, but for more complex comparisons and multiple nested levels use the classic if/else constructs?
share
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C++ templates that accept only certain types
...nable to use your observable_list.
There are two solutions to this issue, one of them is to not constrain anything and rely on duck typing. A big con to this solution is that it involves a massive amount of errors that can be hard for users to grok. Another solution is to define traits to constrain...
How to vertically center a container in Bootstrap?
... support vh unit */
min-height: 100vh; /* These two lines are counted as one :-) */
display: flex;
align-items: center;
}
Important notes (Considered in the demo):
A percentage values of height or min-height properties is relative to the height of the parent element, therefore you s...
Track a new remote branch created on GitHub
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If there is only one remote branch with that branch name, you can just do git checkout <branchname> and git will automatically check it out and setup a tracking branch. Just wanted to reiterate what @Mark Longair said above in this comm...
Using multiple let-as within a if-statement in Swift
...gitudeDouble are non-optional in here
}
Just be sure to remember that if one of the attempted optional bindings fail, the code inside the if-let block won't be executed.
Note: the clauses don't all have to be 'let' clauses, you can have any series of boolean checks separated by commas.
For exam...
How to pretty-print a numpy.array without scientific notation and with given precision?
... @Hiett: There is no NumPy function to set print options for just one print, but you could use a context manager to make something similar. I've edited the post above to show what I mean.
– unutbu
Mar 28 '13 at 15:19
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