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Should I use a data.frame or a matrix?
..., which handles factors appropriately by converting them to numeric values based on the internal levels. Coercing via as.matrix() will result in a character matrix if any of the factor labels is non-numeric. Compare:
> head(as.matrix(data.frame(a = factor(letters), B = factor(LETTERS))))
a ...
Why can't yield return appear inside a try block with a catch?
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My attempt at value initialization is interpreted as a function declaration, and why doesn't A a(())
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When should I use jQuery deferred's “then” method and when should I use the “pipe” method?
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Updating packages in Emacs
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Is R's apply family more than syntactic sugar?
...an be substantial, like when you have to nest for-loops to get the average based on a grouping of more than one factor. Here you have two approaches that give you the exact same result :
set.seed(1) #for reproducability of the results
# The data
X <- rnorm(100000)
Y <- as.factor(sample(lett...
Why doesn't the example compile, aka how does (co-, contra-, and in-) variance work?
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How to add a local repo and treat it as a remote repo
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Covariance, Invariance and Contravariance explained in plain English?
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Java 8: performance of Streams vs Collections
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