isSymmetric-methods {Matrix}R Documentation

Methods for Function isSymmetric in Package 'Matrix'

Description

isSymmetric(M) returns a logical indicating if M is a symmetric matrix. This is a base function with a default method for the traditional matrices of class "matrix". Methods here are defined for virtual Matrix classes such that it works for all objects inheriting from class Matrix.

See Also

forceSymmetric, symmpart, and the formal class (and subclasses) "symmetricMatrix".

Examples

isSymmetric(Diagonal(4)) # TRUE of course
M <- Matrix(c(1,2,2,1), 2,2)
isSymmetric(M) # TRUE (*and* of formal class "dsyMatrix")
isSymmetric(as(M, "dgeMatrix")) # still symmetric, even if not "formally"
isSymmetric(triu(M)) # FALSE

[Package Matrix version 1.0-14 Index]