UPTRI

Purpose:

Returns the upper triangle of a matrix, including the main diagonal.

UPTRI(a)

A matrix.

An array of size(a) consisting of the upper triangle of a, including the main diagonal, with the other elements set to 0.

W1: ones(3)

W2: uptri(W1)

W2 == {{1, 1, 1},

{0, 1, 1},

{0, 0, 1}}

UPTRI includes the main diagonal. Use UPTRIX to exclude the main diagonal.

Use TRIU to return the upper matrix above a specified diagonal.