Matrix (version 1.2-16)

isSymmetric-methods: Methods for Function isSymmetric in Package 'Matrix'

Description

isSymmetric(M) returns a logical indicating if M is a symmetric matrix. This (now) 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

# NOT RUN {
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

## Look at implementations:
showMethods("isSymmetric", includeDefs=TRUE)# "ANY": base's S3 generic; 6 more
# }