R: Calculates the mean for each row (column) in a matrix

rowMeans2 {matrixStats}

R Documentation

Calculates the mean for each row (column) in a matrix

Description

Calculates the mean for each row (column) in a matrix.

Usage

rowMeans2(x, rows = NULL, cols = NULL, na.rm = FALSE, refine = TRUE,
  dim. = dim(x), ..., useNames = TRUE)

colMeans2(x, rows = NULL, cols = NULL, na.rm = FALSE, refine = TRUE,
  dim. = dim(x), ..., useNames = TRUE)

Arguments

`x`	An NxK `matrix` or, if `dim.` is specified, an N * K `vector`.
`rows`	A `vector` indicating subset of rows to operate over. If `NULL`, no subsetting is done.
`cols`	A `vector` indicating subset of columns to operate over. If `NULL`, no subsetting is done.
`na.rm`	If `TRUE`, missing values are excluded.
`refine`	If `TRUE` and `x` is `numeric`, then extra effort is used to calculate the average with greater numerical precision, otherwise not.
`dim.`	An `integer` `vector` of length two specifying the dimension of `x`, also when not a `matrix`. Comment: The reason for this argument being named with a period at the end is purely technical (we get a run-time error if we try to name it `dim`).
`...`	Not used.
`useNames`	If `FALSE` (default), no naming support is done. Else if `TRUE`, names attributes of result are set.

Details

The implementation of rowMeans2() and colMeans2() is optimized for both speed and memory.

Value

Returns a numeric vector of length N (K).

Author(s)

Henrik Bengtsson

[Package matrixStats version 1.0.0 Index]