R: Lower/Upper Triangle Elements of a Matrix

Tri2M {MCMCglmm}

R Documentation

Lower/Upper Triangle Elements of a Matrix

Lower/Upper triangle elements of a matrix or forms a matrix from a vector of lower/upper triangle elements

Tri2M(x, lower.tri = TRUE, reverse = TRUE, diag = TRUE)

`x`	Matrix or vector
`lower.tri`	If `x` is a matrix then the lower triangle (`TRUE`) or upper triangle `FALSE` elements (including diagonal elements) are returned. If `x` is a vector a matrix is formed under the assumption that `x` are the lower triangle (`TRUE`) or upper triangle (`FALSE`) elements.
`reverse`	logical: if`TRUE` a symmetric matrix is formed, if `FALSE` the remaining triangle is left as zeros.
`diag`	logical: if`TRUE` diagonal elements are included.

numeric or matrix

M<-rIW(diag(3), 10)
x<-Tri2M(M)
x
Tri2M(x, reverse=TRUE)
Tri2M(x, reverse=FALSE)

[Package MCMCglmm version 2.36 Index]