colLogSumExps-xgCMatrix-method: Accurately calculates the logarithm of the sum of...

In const-ae/sparseMatrixStats: Summary Statistics for Rows and Columns of Sparse Matrices

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 = TRUE)

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

Arguments

lx	An NxK matrix-like object. Typically lx are log(x) values.
rows, cols	A vector indicating the subset (and/or columns) to operate over. If NULL, no subsetting is done.
na.rm	If TRUE, missing values (NA or NaN) are omitted from the calculations.
useNames	If TRUE (default), names attributes of result are set. Else if FALSE, no naming support is done.

Details

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

Value

Returns a numeric vector of length N (K).

See Also

• matrixStats::rowLogSumExps() and matrixStats::colLogSumExps() which are used when the input is a matrix or numeric vector.

• rowSums2()

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)

const-ae/sparseMatrixStats documentation built on April 12, 2025, 11:58 p.m.