collapse_matrix: Collapse matrix

In surh/AMOR: Abundance Matrix Operations in R

Collapse matrix

Description

Takes a two-dimensional matrix and collapses row or columns according to a specified function.

Usage

collapse_matrix(x, groups, dim = 1, FUN = sum)

Arguments

x	A matrix object.
groups	A vector or factor of the same length as the rows or columns of x, which indicates which elements to collapse.
dim	Which dimension to collapse. 1 for rows and 2 for columns
FUN	Function (or function name) to apply to elements per groups

Details

This function uses plyr functions to aggregate columnwise or rowwise according to a grouping factor.

Value

Returns a matrix object.

Author(s)

Sur Herrera Paredes

Examples

x <- cbind(rbind(matrix(0,2,2),matrix(1,2,2)),
           rbind(matrix(1,2,2),matrix(0,2,2)))
colnames(x) <- c("C1","C2","C3","C4")
row.names(x) <- c("R1","R2","R3","R4")

x
collapse_matrix(x=x,groups = rep(c(1,2),each=2),dim=1,FUN=sum)
collapse_matrix(x=x,groups = rep(c(1,2),each=2),dim=2,FUN=mean)

surh/AMOR documentation built on Feb. 21, 2023, 6:31 a.m.