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How to drop columns by name in a data frame
...ubset function. For example :
R> df <- data.frame(x=1:5, y=2:6, z=3:7, u=4:8)
R> df
x y z u
1 1 2 3 4
2 2 3 4 5
3 3 4 5 6
4 4 5 6 7
5 5 6 7 8
Then you can use the which function and the - operator in column indexation :
R> df[ , -which(names(df) %in% c("z","u"))]
x y
1 1 2
2 2 3
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How to check if a string contains an element from a list in Python
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– Lauritz V. Thaulow
May 31 '14 at 23:47
5
And if I want to know what ext is when any() returns True...
Do you have to put Task.Run in a method to make it async?
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597
First, let's clear up some terminology: "asynchronous" (async) means that it may yield control b...
Would it be beneficial to begin using instancetype instead of id?
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answered Jan 23 '12 at 18:47
Catfish_ManCatfish_Man
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prototype based vs. class based inheritance
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edited Nov 19 '13 at 17:19
tig
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answered Ma...
Difference of keywords 'typename' and 'class' in templates?
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447
typename and class are interchangeable in the basic case of specifying a template:
template<...
Why am I merging “remote-tracking branch 'origin/develop' into develop”?
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edited May 23 '17 at 12:34
Community♦
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answered Jun 20 '11 at 4:55
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Update Item to Revision vs Revert to Revision
...copy which were made after the selected revision (in your example rev. 96,97,98,99,100)
Your working copy is now in modified state.
The file content of both scenarions is same, however in first case you have an unmodified working copy and you cannot commit your changes(as your workingcopy is not p...
Add legend to ggplot2 line plot
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answered Apr 27 '12 at 10:57
csgillespiecsgillespie
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Is it safe to ignore the possibility of SHA collisions in practice?
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Arslan Ali
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answered Oct 25 '10 at 12:14
Thomas PorninThomas...