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Convert a list of data frames into one data frame
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since it's 2018 and dplyr is both fast and a solid tool to use, I've changed this to the accepted answer. The years, they fly by!
– JD Long
Jan 12 '19 at 12:03
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Can I specify multiple users for myself in .gitconfig?
... You can manually edit those config files with git config --edit and git config --global --edit. And in case you missed Abizern’s comment, a repository’s config file is at <repo-root>/.git/config.
– Rory O'Kane
Apr 25 '12 at 20:01
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What is the reason for having '//' in Python? [duplicate]
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In Python 3, they made the / operator do a floating-point division, and added the // operator to do integer division (i.e. quotient without remainder); whereas in Python 2, the / operator was simply integer division, unless one of the operands was already a floating point number.
In Python 2...
Difference between no-cache and must-revalidate
...st-Modified, the agent has nothing to use to validate what it has in cache and must download the whole payload again. So when the RFC says "revalidate" that probably means, re-fetch.
– Luke Puplett
Nov 13 '13 at 11:55
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Pandas: drop a level from a multi-level column index?
... If the index you are trying to drop is on the left (row) side and not the top (column) side, you can change "columns" to "index" and use the same method: >>> df.index = df.index.droplevel(1)
– Idodo
Nov 28 '18 at 12:13
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Case preserving substitute in Vim
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We do not deserve Tim Pope.
– Andrew Keeton
May 23 '19 at 19:47
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This plu...
CGContextDrawImage draws image upside down when passed UIImage.CGImage
...GContextDrawImage method gets the underlying raw image data with no understanding of orientation.
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Is < faster than
...n two machine instructions:
A test or cmp instruction, which sets EFLAGS
And a Jcc (jump) instruction, depending on the comparison type (and code layout):
jne - Jump if not equal --> ZF = 0
jz - Jump if zero (equal) --> ZF = 1
jg - Jump if greater --> ZF = 0 and SF = OF
(etc...)
Exa...
Putting an if-elif-else statement on one line?
...itting everything on one line would most likely violate PEP-8 where it is mandated that lines should not exceed 80 characters in length.
It's also against the Zen of Python: "Readability counts". (Type import this at the Python prompt to read the whole thing).
You can use a ternary expression in P...
(-2147483648> 0) returns true in C++?
...uld make the compiler to evaluate -2147483648 in the domain of larger type and the result would be negative, as one would expect.
However, apparently in your case the range of long int is the same as range of int, and in general there's no integer type with greater range than int on your platform....