usd {MESS}

Unbiased standard deviation

Description

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

Usage

usd(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.

Value

A scalar

Examples

sd(1:5)
usd(1:5)