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cartesian product in pandas
...port DataFrame, merge
df1 = DataFrame({'key':[1,1], 'col1':[1,2],'col2':[3,4]})
df2 = DataFrame({'key':[1,1], 'col3':[5,6]})
merge(df1, df2,on='key')[['col1', 'col2', 'col3']]
Output:
col1 col2 col3
0 1 3 5
1 1 3 6
2 2 4 5
3 2 4 6
See here f...
What is the difference between jQuery's mouseout() and mouseleave()?
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How to rollback just one step using rake db:migrate
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edited Jul 22 '14 at 15:58
answered Dec 4 '10 at 9:43
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How can I get maven-release-plugin to skip my tests?
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406
-Darguments="-DskipTests" is what you want, or explicitly configuring the forked executions in...
Foreign key from one app into another in Django
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answered Nov 27 '08 at 14:27
Michael WarkentinMichael Warkentin
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How to stop Visual Studio from opening a file on single click?
...tsrubber boots
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125
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How to find the length of a string in R
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424
See ?nchar. For example:
> nchar("foo")
[1] 3
> set.seed(10)
> strn <- paste(samp...
List files in local git repo?
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Cory Klein
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answered Dec 16 '11 at 11:16
karlphillipkarlp...
How do I test which class an object is in Objective-C?
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344
To test if object is an instance of class a:
[yourObject isKindOfClass:[a class]]
// Returns a...