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Upper Triangular Part of a Matrix
 Syntax `triu(`A```) triu(```A`, `k`)` See Also tril , diag , identity

Description
The syntax `triu(`A`)` returns the upper triangular part of A ``` ```The syntax `triu(`X`,`k`)` returns the elements on and above the k-th diagonal of A where k is an integer, real or double-precision scalar. The value `k = 0` corresponds to the main diagonal, `k > 0` corresponds to above the main diagonal, and `k < 0` corresponds to below the main diagonal.

Example:
If you enter ```      A = {[1, 2], [3, 4]}      triu(A) ``` O-Matrix will respond ```      {      [ 1 , 2 ]      [ 0 , 4 ]      } ``` If you enter ```      A = {[1, 2 , 3], [4, 5, 6], [7, 8, 9]}      k = 1      triu(A, k) ``` O-Matrix will respond ```      {      [ 0 , 2 , 3 ]      [ 0 , 0 , 6 ]      [ 0 , 0 , 0 ]      } ```