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, i.e., extraction or subsetting mostly of
matrices, in package [<--methods
for subassignment to "Matrix"
objects.
Extract
about the standard extraction.str(m <- Matrix(round(rnorm(7*4),2), nrow = 7))
stopifnot(identical(m, m[]))
m[2, 3] # simple number
m[2, 3:4] # simple numeric of length 2
m[2, 3:4, drop=FALSE] # sub matrix of class 'dgeMatrix'
## rows or columns only:
m[1,] # first row, as simple numeric vector
m[,1:2] # sub matrix of first two columns
showMethods("[", inherited = FALSE)
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