rowSums2 {matrixStats}

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

Description

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

Usage

rowSums2(x, rows = NULL, cols = NULL, na.rm = FALSE, dim. = dim(x),
  ..., useNames = TRUE)

colSums2(x, rows = NULL, cols = NULL, na.rm = FALSE, dim. = dim(x),
  ..., useNames = TRUE)

Arguments

x

An NxK matrix or, if dim. is specified, an N * K vector.

rows

A vector indicating subset of rows to operate over. If NULL, no subsetting is done.

cols

A vector indicating subset of columns to operate over. If NULL, no subsetting is done.

na.rm

If TRUE, missing values are excluded.

dim.

An integer vector of length two specifying the dimension of x, also when not a matrix. Comment: The reason for this argument being named with a period at the end is purely technical (we get a run-time error if we try to name it dim).

...

Not used.

useNames

If TRUE (default), names attributes of the result are set, otherwise not.

Details

The implementation of rowSums2() and colSums2() is optimized for both speed and memory.

Value

Returns a numeric vector of length N (K).

Author(s)

Henrik Bengtsson