colamdR {edmcr}

Column Approximate Minimum Degree Permutation

Description

colamdR returns the column approximate minimum degree permutation of a sparse matrix S. The permutation of S, S[,p], will result in LU factors sparser than S.

Usage

colamdR(M)

Arguments

M

A matrix to be permuted.

Details

This is an implementation of the colamd function available in SuiteSparse, and also implemented in Matlab.

Value

A vector containing the column minimum degree permutation of the matrix M.

References

The authors of the code for "colamd" are Stefan I. Larimore and Timothy A. Davis ([e-mail]), University of Florida.

Examples

M <- matrix(c(1,1,0,0,1,0,0,1,0,1,1,1,1,1,0,0,1,0,1,0), ncol=4)
p <- colamdR(M)
M[,p]