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stats (version 3.3.2)

sd: Standard Deviation

Description

This function computes the standard deviation of the values in x. If na.rm is TRUE then missing values are removed before computation proceeds.

Usage

sd(x, na.rm = FALSE)

Arguments

x
a numeric vector or an R object which is coercible to one by as.double(x).
na.rm
logical. Should missing values be removed?

Details

Like var this uses denominator \(n - 1\). The standard deviation of a zero-length vector (after removal of NAs if na.rm = TRUE) is not defined and gives an error. The standard deviation of a length-one vector is NA.

See Also

var for its square, and mad, the most robust alternative.

Examples

Run this code
sd(1:2) ^ 2

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