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How to fix the uninitialized constant Rake::DSL problem on Heroku?
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KaleKale
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Getting the count of unique values in a column in bash
...e.Paused until further notice.
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Why can't R's ifelse statements return vectors?
...s, you will get longer results:
> ifelse(c(TRUE, FALSE), c(1, 2), c(3, 4))
[1] 1 4
So ifelse is intended for the specific purpose of testing a vector of booleans and returning a vector of the same length, filled with elements taken from the (vector) yes and no arguments.
It is a common confus...
How to escape a single quote inside awk
... fedorqui 'SO stop harming'
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answered Mar 28 '12 at 0:31
SteveSteve
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Setting JDK in Eclipse
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146
You manage the list of available compilers in the Window -> Preferences -> Java -> Ins...
For each row return the column name of the largest value
...ample reproducible):
DF <- data.frame(V1=c(2,8,1),V2=c(7,3,5),V3=c(9,6,4))
colnames(DF)[apply(DF,1,which.max)]
[1] "V3" "V1" "V2"
A faster solution than using apply might be max.col:
colnames(DF)[max.col(DF,ties.method="first")]
#[1] "V3" "V1" "V2"
...where ties.method can be any of "rando...
Order data frame rows according to vector with specific order
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Try match:
df <- data.frame(name=letters[1:4], value=c(rep(TRUE, 2), rep(FALSE, 2)))
target <- c("b", "c", "a", "d")
df[match(target, df$name),]
name value
2 b TRUE
3 c FALSE
1 a TRUE
4 d FALSE
It will work as long as your target contains exactly...
invalid multibyte char (US-ASCII) with Rails and Ruby 1.9
I'm using Ruby 1.9.1 with Rails 2.3.4 My application is to handle text input
6 Answers
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How do I tell Matplotlib to create a second (new) plot, then later plot on the old one?
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