colLogSumExps,xgCMatrix-method {sparseMatrixStats}R Documentation

Accurately calculates the logarithm of the sum of exponentials for each row (column) of a matrix-like object

Description

Accurately calculates the logarithm of the sum of exponentials for each row (column) of a matrix-like object.

Usage

## S4 method for signature 'xgCMatrix'
colLogSumExps(lx, rows = NULL, cols = NULL, na.rm = FALSE, useNames = NA)

## S4 method for signature 'xgCMatrix'
rowLogSumExps(lx, rows = NULL, cols = NULL, na.rm = FALSE, useNames = NA)

Arguments

lx

An NxK matrix-like object. Typically lx are log(x) values.

rows

A vector indicating the subset (and/or columns) to operate over. If NULL, no subsetting is done.

cols

A vector indicating the subset (and/or columns) to operate over. If NULL, no subsetting is done.

na.rm

If TRUE, NAs are excluded first, otherwise not.

useNames

If NA, the default behavior of the function about naming support is remained. If FALSE, no naming support is done. Else if TRUE, names attributes of result are set.

Details

The S4 methods for x of type matrix, array, or numeric call matrixStats::rowLogSumExps / matrixStats::colLogSumExps.

Value

Returns a numeric vector of length N (K).

See Also

Examples

mat <- matrix(rnorm(15), nrow = 5, ncol = 3)
  mat[2, 1] <- NA
  mat[3, 3] <- Inf
  mat[4, 1] <- 0
  
  print(mat)
  
  rowLogSumExps(mat)
  colLogSumExps(mat)

[Package sparseMatrixStats version 1.4.2 Index]