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Open and write data to text file using Bash?
...x number of file descriptors the kernel can allocate can be found in /proc/sys/file-max or /proc/sys/fs/file-max but using any fd above 9 is dangerous as it could conflict with fd's used by the shell internally. So don't bother and only use fd's 0-9. If you need more the 9 file descriptors in a bash...
How to convert index of a pandas dataframe into a column?
This seems rather obvious, but I can't seem to figure out how to convert an index of data frame to a column?
7 Answers
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SQL query to group by day
...
actually this depends on what DBMS you are using but in regular SQL convert(varchar,DateColumn,101) will change the DATETIME format to date (one day)
so:
SELECT
sum(amount)
FROM
sales
GROUP BY
convert(varchar,created,101)
the magix number 101 is what date format it is con...
Convert pandas timezone-aware DateTimeIndex to naive timestamp, but in certain timezone
...DateTimeIndex timezone aware, but how can you do the opposite: how can you convert a timezone aware Timestamp to a naive one, while preserving its timezone?
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Extension methods must be defined in a non-generic static class
... Beware that you may get this compiler if you inadvertently converted your class to an extension method (according to the compiler). See this answer with regards to static methods and this answer with regards to this method arguments.
– Maarten Bodewes
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What’s the best way to check if a file exists in C++? (cross platform)
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Use boost::filesystem:
#include <boost/filesystem.hpp>
if ( !boost::filesystem::exists( "myfile.txt" ) )
{
std::cout << "Can't find my file!" << std::endl;
}
...
Get Output From the logging Module in IPython Notebook
...rding to logging.basicConfig:
Does basic configuration for the logging system by creating a
StreamHandler with a default Formatter and adding it to the root
logger. The functions debug(), info(), warning(), error() and
critical() will call basicConfig() automatically if no handlers are
d...
How to get the ASCII value of a character
...ion ord() would get the int value
of the char. And in case you want to
convert back after playing with the
number, function chr() does the trick.
>>> ord('a')
97
>>> chr(97)
'a'
>>> chr(ord('a') + 3)
'd'
>>>
In Python 2, there is also the unichr function...
Exiting from python Command Line
... what you do on Windows (well, DOS) where you would do Ctrl-D on Unix-like systems.
– Karl Knechtel
Mar 16 '12 at 1:10
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OpenCV C++/Obj-C: Detecting a sheet of paper / Square Detection
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Unless there is some other requirement not specified, I would simply convert your color image to grayscale and work with that only (no need to work on the 3 channels, the contrast present is too high already). Also, unless there is some specific problem regarding resizing, I would work with a ...