lower.tri
Logical Matrix of the Lower or Upper Triangle
Description
Return a matrix of logical values the same size as the input matrix
specified in the x argument. The lower or upper triangle
contain TRUE; all other values contain FALSE.
Usage
lower.tri(x, diag = FALSE)
upper.tri(x, diag = FALSE)
Arguments
x |
a matrix.
|
diag |
a logical value. If TRUE, the diagonal elements are
included in the triangle.
|
Value
returns a matrix of the same dimension as x. In the case of a
lower triangle, the elements above the diagonal return FALSE and
the elements below the diagonal return TRUE. The value of the
diagonal elements depends on what you specify for the diag
argument.
See Also
Examples
lower.tri(Sdatasets::freeny.x)
upper.tri(Sdatasets::freeny.x, T)
# A correlation matrix with 0.5 on all off-diagonals:
corr <- diag(5)
corr[lower.tri(corr)] <- 0.5
corr[upper.tri(corr)] <- 0.5
corr