tril (MATLAB Function Reference)

tril	Examples See Also

Lower triangular part of a matrix

Syntax

L = tril(X)
L = tril(X,k)

Description

L = tril(X)

returns the lower triangular part of X.

L = tril(X,k)

returns the elements on and below the kth diagonal of X. k = 0 is the main diagonal, k > 0 is above the main diagonal, and k < 0 is below the main diagonal.

Examples

tril(ones(4,4),-1) is

    0    0    0    0
    1    0    0    0
    1    1    0    0
    1    1    1    0