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

colMeans2 {DelayedMatrixStats}

R Documentation

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

Description

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

Usage

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

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

## S4 method for signature 'DelayedMatrix'
colMeans2(
  x,
  rows = NULL,
  cols = NULL,
  na.rm = FALSE,
  dim. = dim(x),
  force_block_processing = FALSE,
  ...
)

## S4 method for signature 'Matrix'
colMeans2(x, rows = NULL, cols = NULL, na.rm = FALSE, dim. = dim(x), ...)

## S4 method for signature 'SolidRleArraySeed'
colMeans2(x, rows = NULL, cols = NULL, na.rm = FALSE, dim. = dim(x), ...)

## S4 method for signature 'DelayedMatrix'
rowMeans2(
  x,
  rows = NULL,
  cols = NULL,
  na.rm = FALSE,
  dim. = dim(x),
  force_block_processing = FALSE,
  ...
)

## S4 method for signature 'Matrix'
rowMeans2(x, rows = NULL, cols = NULL, na.rm = FALSE, dim. = dim(x), ...)

Arguments

`x`	A NxK DelayedMatrix.
`rows`	A `vector` indicating subset of rows (and/or columns) to operate over. If `NULL`, no subsetting is done.
`cols`	A `vector` indicating subset of rows (and/or columns) to operate over. If `NULL`, no subsetting is done.
`na.rm`	If `TRUE`, `NA`s are excluded first, otherwise not.
`dim.`	An `integer` `vector` of length two specifying the dimension of `x`, also when not a `matrix`.
`...`	Additional arguments passed to specific methods.
`force_block_processing`	`FALSE` (the default) means that a seed-aware, optimised method is used (if available). This can be overridden to use the general block-processing strategy by setting this to `TRUE` (typically not advised). The block-processing strategy loads one or more (depending on `\link[DelayedArray]{getAutoBlockSize}()`) columns (`colFoo()`) or rows (`rowFoo()`) into memory as an ordinary base::array.

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)

Peter Hickey

Examples

# A DelayedMatrix with a 'matrix' seed
dm_matrix <- DelayedArray(matrix(c(rep(1L, 5),
                                   as.integer((0:4) ^ 2),
                                   seq(-5L, -1L, 1L)),
                                 ncol = 3))
# A DelayedMatrix with a 'SolidRleArraySeed' seed
dm_Rle <- RleArray(Rle(c(rep(1L, 5),
                         as.integer((0:4) ^ 2),
                         seq(-5L, -1L, 1L))),
                   dim = c(5, 3))

colMeans2(dm_matrix)

# NOTE: Temporarily use verbose output to demonstrate which method is
#       which method is being used
options(DelayedMatrixStats.verbose = TRUE)
# By default, this uses a seed-aware method for a DelayedMatrix with a
# 'SolidRleArraySeed' seed
rowMeans2(dm_Rle)
# Alternatively, can use the block-processing strategy
rowMeans2(dm_Rle, force_block_processing = TRUE)
options(DelayedMatrixStats.verbose = FALSE)

[Package DelayedMatrixStats version 1.10.1 Index]