R: (Weighted) Standard Deviation

SD {DescTools} | R Documentation

## (Weighted) 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, weights = NULL, na.rm = FALSE, ...)

### Arguments

`x` | a numeric vector or an R object which is coercible to one by `as.double(x)`.
`weights` | a numerical vector of weights the same length as `x` giving the weights to use for elements of `x`.
`na.rm` | logical. Should missing values be removed?
`...` | further arguments passed to or from other methods.

### Details

Like `var` this uses denominator n - 1.

The standard deviation of a zero-length vector (after removal of `NA`s 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

    SD(1:2)^2

[Package DescTools version 0.99.34 Index]