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How to count the frequency of the elements in an unordered list?
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@CristianCiupitu: sum(1 for _ in group).
– Martijn Pieters♦
Jul 29 '16 at 7:25
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How to rename a single column in a data.frame?
...r.name'
This code pretty much does the following:
names(df) looks into all the names in the df
[names(df) == old.var.name] extracts the variable name you want to check
<- 'new.var.name' assigns the new variable name.
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How do you run a crontab in Cygwin on Windows?
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You need to also install cygrunsrv so you can set cron up as a windows service, then run cron-config.
If you want the cron jobs to send email of any output you'll also need to install either exim or ssmtp (before running cron-config.)
See /usr/...
Is there a built in function for string natural sort?
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There is a third party library for this on PyPI called natsort (full disclosure, I am the package's author). For your case, you can do either of the following:
>>> from natsort import natsorted, ns
>>> x = ['Elm11', 'Elm12', 'Elm2', 'elm0', 'elm1', 'elm1...
How can I convert an RGB image into grayscale in Python?
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SciPy's image I/O is literally PIL/Pillow. Hence, testing SciPy is effectively retesting PIL/Pillow with negligible overhead introduced by SciPy's wrapper functions. It would have been much more useful to substitute OpenCV (which does not leverage PIL...
Flex-box: Align last row to grid
...d:after and it works the same. Now if you tried something like this it totally breaks. Notice the widths for each set of 4 dont add up to 100%. In the OP's fiddle the widths are set in px so your solution doesn't work this situation.
– Jacob
Jan 26 '16 at 15...
What is the motivation for bringing Symbols to ES6?
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Most languages (all mainstream ones afaik) provide some mechanism, usually reflection, to get access to private anyway.
– Esailija
May 14 '14 at 10:58
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pandas: multiple conditions while indexing data frame - unexpected behavior
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You can use query(), i.e.:
df_filtered = df.query('a == 4 & b != 2')
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“Failed to load platform plugin ”xcb“ ” while launching qt5 app on linux without qt installed
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In my case sudo apt-get install libx11-xcb1 fixed the problem. But your recommendation of using ldd was what pointed me to the correct library to install. Thanks!
– Daniel
Mar 17 '15 at 0:37
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ARC and bridged cast
...__bridge_transfer? Otherwise it would seem that the moment CFRelease() is called the object is gone and points to nothing. Similarly, when you use __bridge_retain, does ARC reduce the op's retain count by 1? Else it seems that the object would never be properly released.
– Tony...