sd: Standard Deviation

sdR Documentation

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 but not a factor coercible to numeric 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 length-one or zero-length vector is NA.

See Also

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

Examples

sd(1:2) ^ 2