matrixStats: rowLogSumExps – R documentation

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matrixStats

rowLogSumExps

Accurately computes the logarithm of the sum of exponentials across rows or columns

Description

Accurately computes the logarithm of the sum of exponentials across rows or columns.

Usage

rowLogSumExps(lx, rows = NULL, cols = NULL, na.rm = FALSE, dim. = dim(lx), ...)

colLogSumExps(lx, rows = NULL, cols = NULL, na.rm = FALSE, dim. = dim(lx), ...)

Arguments

`lx`	A `numeric` NxK `matrix`. Typically `lx` are log(x) values.
`rows, cols`	A `vector` indicating subset of rows (and/or columns) to operate over. If `NULL`, no subsetting is done.
`na.rm`	If `TRUE`, any missing values are ignored, otherwise not.
`dim.`	An `integer` `vector` of length two specifying the dimension of `x`, also when not a `matrix`.
`...`	Not used.

Value

A numeric vector of length N (K).

Benchmarking

These methods are implemented in native code and have been optimized for speed and memory.

Author(s)

Native implementation by Henrik Bengtsson. Original R code by Nakayama ??? (Japan).