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Recommended way to stop a Gradle build
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edited Jan 1 '17 at 20:45
Pokechu22
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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:
l...
How can I clear the SQL Server query cache?
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answered Dec 9 '09 at 10:45
SaarSaar
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For files in directory, only echo filename (no path)
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SiegeXSiegeX
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Why can I pass 1 as a short, but not the int variable i?
...esInChaos
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Turn a simple socket into an SSL socket
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Overlaying histograms with ggplot2 in R
... with some output:
dat <- data.frame(xx = c(runif(100,20,50),runif(100,40,80),runif(100,0,30)),yy = rep(letters[1:3],each = 100))
ggplot(dat,aes(x=xx)) +
geom_histogram(data=subset(dat,yy == 'a'),fill = "red", alpha = 0.2) +
geom_histogram(data=subset(dat,yy == 'b'),fill = "blue", alph...