# colVars: Column variances In asuR: Advanced statistics using R

## Description

Form column variances for numeric arrays

## Usage

 `1` ```colVars(x, na.rm = FALSE, dims = 1, unbiased = TRUE, SumSquares = FALSE, twopass = FALSE) ```

## Arguments

 `x` A numeric array (or a dataframe to convert to a matrix) `na.rm` Logical: Remove NA's (not available values) `dims` Number of dimensions to sum over [colSums] or leave alone [rowSums]. Only useful when x is a multidimensional array `unbiased` Logical: Use (N-1) in the denominator when calculating variance `SumSquares` Logical: If TRUE, colVars just returns sums of squares. `twopass` Logical: If TRUE, colVars uses the corrected two-pass algorithm of Chan Golub & LeVeque, which is slower but less subject to roundoff error.

## Value

A vector with the variance for every column.

## Author(s)

colVars: Originally by Douglas Bates <[email protected]> as package "MatUtils". Modified, expanded, and renamed by David Brahm <[email protected]>, with help of course from the R-help gurus.

`colMeans`
 ```1 2 3 4 5 6``` ```mat <- cbind(rnorm(100, sd=sqrt(1)), rnorm(100, sd=sqrt(2)), rnorm(100, sd=sqrt(3)), rnorm(100, sd=sqrt(4)), rnorm(100, sd=sqrt(5))) colVars(mat) ```