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How to find where gem files are installed
...t about your gem environment:
RubyGems Environment:
- RUBYGEMS VERSION: 2.1.5
- RUBY VERSION: 2.0.0 (2013-06-27 patchlevel 247) [x86_64-darwin12.4.0]
- INSTALLATION DIRECTORY: /Users/ttm/.rbenv/versions/2.0.0-p247/lib/ruby/gems/2.0.0
- RUBY EXECUTABLE: /Users/ttm/.rbenv/versions/2.0.0-p247/...
Call apply-like function on each row of dataframe with multiple arguments from each row
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C++ preprocessor __VA_ARGS__ number of arguments
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How do I replace NA values with zeros in an R dataframe?
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Is it possible to use 'else' in a list comprehension? [duplicate]
... c. It can be used in comprehension statements:
>>> [a if a else 2 for a in [0,1,0,3]]
[2, 1, 2, 3]
So for your example,
table = ''.join(chr(index) if index in ords_to_keep else replace_with
for index in xrange(15))
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What is the difference between String.slice and String.substring?
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slice() works like substring() with a few different behaviors.
Syntax: string.slice(start, stop...
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...
What ReSharper 4+ live templates for C# do you use? [closed]
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Virtualbox “port forward” from Guest to Host [closed]
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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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