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| triu | Examples See Also |
Upper triangular part of a matrix
U = triu(X) U = triu(X,k)
U = triu(X)
returns the upper triangular part of X.
U = triu(X,k)
returns the element on and above 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.
triu(ones(4,4),-1) is
1 1 1 1
1 1 1 1
0 1 1 1
0 0 1 1
diag Diagonal matrices and diagonals of a matrix
tril Lower triangular part of a matrix