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Selecting multiple columns in a pandas dataframe
...).
df1 = df[['a', 'b']]
Alternatively, if it matters to index them numerically and not by their name (say your code should automatically do this without knowing the names of the first two columns) then you can do this instead:
df1 = df.iloc[:, 0:2] # Remember that Python does not slice inclusive of...
How do I convert Word files to PDF programmatically? [closed]
I have found several open-source/freeware programs that allow you to convert .doc files to .pdf files, but they're all of the application/printer driver variety, with no SDK attached.
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Curly braces in string in PHP
...nterpolation. From the manual:
Complex (curly) syntax
This isn't called complex because the syntax is complex, but because
it allows for the use of complex expressions.
Any scalar variable, array element or object property with a string
representation can be included via this synta...
Turn a string into a valid filename?
I have a string that I want to use as a filename, so I want to remove all characters that wouldn't be allowed in filenames, using Python.
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How can I find the number of arguments of a Python function?
...ms = sig.parameters
print(params['kwarg1']) # prints: kwarg1=20
Additionally, you can call len on sig.parameters to also see the number of arguments this function requires:
print(len(params)) # 3
Each entry in the params mapping is actually a Parameter object that has further attributes makin...
Standardize data columns in R
I have a dataset called spam which contains 58 columns and approximately 3500 rows of data related to spam messages.
15 ...
关于 __VA_ARGS__ 宽字符版本的问题 - C/C++ - 清泛网 - 专注C/C++及内核技术
关于 __VA_ARGS__ 宽字符版本的问题在写一个可变参数的记录日志函数，考虑到宽字符（Unicode版本）时：#define WIDEN2(x) L ## x#define WIDEN(x) WIDEN2(x)#define __...在写一个可变参数的记录日志函数，考虑到宽字符（Unicode版本）时：
#defin...
Python, Unicode, and the Windows console
...at's the best way around this? Is there any way I can make Python automatically print a ? instead of failing in this situation?
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How to extract the year from a Python datetime object?
...ew times and you'll be prompted with the members of the "now" object:
now.__add__ now.__gt__ now.__radd__ now.__sub__ now.fromordinal now.microsecond now.second now.toordinal now.weekday
now.__class__ now.__hash__ ...
How can I distribute python programs?
...ugh I don't know how it works on Windows. You would on Windows have to install Python separately if you use distutils, in any case.
I'd probably recommend that you distribute it with disutils for Linux, and Py2exe or something similar for Windows. For OS X I don't know. If it's an end user applicat...