| isSymmetric {base} | R Documentation |
Test if a Matrix or other Object is Symmetric
Description
Generic function to test if object is symmetric or not.
Currently only a matrix method is implemented.
Usage
isSymmetric(object, ...)
## S3 method for class 'matrix'
isSymmetric(object, tol = 100 * .Machine$double.eps, ...)
Arguments
object |
any R object; a |
tol |
numeric scalar >= 0. Smaller differences are not
considered, see |
... |
further arguments passed to methods; the matrix method
passes these to |
Details
The matrix method is used inside eigen by
default to test symmetry of matrices up to rounding error, using
all.equal. It might not be appropriate in all
situations.
Value
logical indicating if object is symmetric or not.
See Also
eigen which calls isSymmetric when its
symmetric argument is missing, as per default.
Examples
isSymmetric(D3 <- diag(3)) # -> TRUE
D3[2,1] <- 1e-100
D3
isSymmetric(D3) # TRUE
isSymmetric(D3, tol = 0) # FALSE for zero-tolerance