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C++ preprocessor __VA_ARGS__ number of arguments
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What is the difference between String.slice and String.substring?
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882
slice() works like substring() with a few different behaviors.
Syntax: string.slice(start, stop...
Numbering rows within groups in a data frame
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Use ave, ddply, dplyr or data.table:
df$num <- ave(df$val, df$cat, FUN = seq_along)
or:
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Two versions of python on linux. how to make 2.7 the default
...ed by #! /usr/bin/env python. You can usually get away with running Python 2.6 scripts in 2.7, but do you want to risk it?
On top of that, monkeying with /usr/bin can break your package manager's ability to manage packages. And changing the order of directories in your PATH will affect a lot of oth...
How to split a string in shell and get the last field
Suppose I have the string 1:2:3:4:5 and I want to get its last field ( 5 in this case). How do I do that using Bash? I tried cut , but I don't know how to specify the last field with -f .
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Converting integer to binary in python
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TrebledJ
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answered May 2 '12 at 9:32
eumiroeumiro
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How do I replace NA values with zeros in an R dataframe?
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Check if all elements in a list are identical
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How do I check if a string is unicode or ascii?
...Unicode characters. There is a bytes type that holds raw bytes.
In Python 2, a string may be of type str or of type unicode. You can tell which using code something like this:
def whatisthis(s):
if isinstance(s, str):
print "ordinary string"
elif isinstance(s, unicode):
pri...
get list of pandas dataframe columns based on data type
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