R: Accurately computes the logarithm of the sum of exponentials...

rowLogSumExps {matrixStats} | R Documentation

## 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), ..., useNames = NA)

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

### 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.
`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.

### 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).

### See Also

To calculate the same on vectors, `logSumExp`().

[Package matrixStats version 0.61.0 Index]