base (version 3.3)

lower.tri: Lower and Upper Triangular Part of a Matrix

Description

Returns a matrix of logicals the same size of a given matrix with entries TRUE in the lower or upper triangle.

Usage

lower.tri(x, diag = FALSE)
upper.tri(x, diag = FALSE)

Arguments

x

a matrix.

diag

logical. Should the diagonal be included?

See Also

diag, matrix.

Examples

(m2 <- matrix(1:20, 4, 5))
lower.tri(m2)
m2[lower.tri(m2)] <- NA
m2