is.diagonal.matrix {matrixcalc} | R Documentation |
Test for diagonal square matrix
Description
This function returns TRUE
if the given matrix argument x
is a square numeric matrix and that the off-diagonal elements are close
to zero in absolute value to within the given tolerance level. Otherwise,
a FALSE
value is returned.
Usage
is.diagonal.matrix(x, tol = 1e-08)
Arguments
x |
a numeric square matrix |
tol |
a numeric tolerance level usually left out |
Value
A TRUE or FALSE value.
Author(s)
Frederick Novomestky fnovomes@poly.edu
References
Bellman, R. (1987). Matrix Analysis, Second edition, Classics in Applied Mathematics, Society for Industrial and Applied Mathematics.
Horn, R. A. and C. R. Johnson (1990). Matrix Analysis, Cambridge University Press.
Examples
A <- diag( 1, 3 )
is.diagonal.matrix( A )
B <- matrix( c( 1, 2, 3, 4 ), nrow=2, byrow=TRUE )
is.diagonal.matrix( B )
C <- matrix( c( 1, 0, 0, 0 ), nrow=2, byrow=TRUE )
is.diagonal.matrix( C )
[Package matrixcalc version 1.0-6 Index]