TriU

Return a copy of a matrix with the elements below the k-th diagonal zeroed. Upper triangular matrix.

matrix matrix::Triu(
const int ndiag=0 // index of diagonal
);

Parameters

ndiag=0

[in] Diagonal below which to zero elements. ndiag = 0 (the default) is the main diagonal, ndiag < 0 is below it and ndiag > 0 is above.

MQL5 example:

   matrix a={{1,2,3},{4,5,6},{7,8,9},{10,11,12}};
   matrix b=a.TriU(-1);
   Print("matrix b \n",b);

  /*
  matrix b
  [[1,2,3]
   [4,5,6]
   [0,8,9]
   [0,0,12]]
  */

Python example:

import numpy as np

a=np.triu([[1,2,3],[4,5,6],[7,8,9],[10,11,12]], -1)
print(a)

[[ 1  2  3]
[ 4  5  6]
[ 0  8  9]
[ 0  0 12]]