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DescTools (version 0.99.19)

Unwhich: Inverse Which

Description

The inverse function to which creates a logical vector/matrix from indices.

Usage

Unwhich(idx, n, useNames = TRUE)

Arguments

idx
the indices as returned by which.

n
integer, the length of the original vector.

useNames
logical, determining if the names of the indices should be preserved.

Value

TRUE on the positions i.

References

http://stackoverflow.com/questions/7659833/inverse-of-which

See Also

which

Examples

Run this code
ll <- c(TRUE, FALSE, TRUE, NA, FALSE, FALSE, TRUE)
names(ll) <- letters[seq(ll)]
i <- which(ll)
# back again (loosing the names of the FALSEs)
Unwhich(i, length(ll))

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