/*****************************************************************************
*                                                                            *
*   UPTRI.SPL    Copyright (C) 2000 DSP Development Corporation              *
*                               All Rights Reserved                          *
*                                                                            *
*   Author:      Randy Race                                                  *
*                                                                            *
*   Synopsis:    Returns the upper triangle of an array                      *
*                                                                            *
*   Revisions:    3 Apr 2000  RRR  Creation - from MATRIX.MAC by             *
*                                             Kevin Carmondy                 *
*                                                                            *
*****************************************************************************/

#if @HELP_UPTRI

    UPTRI

    Purpose: Returns the upper triangle of a matrix including the main diagonal

    Syntax:  UPTRI(m)

                  m -  input array


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

    Example:
             W1: ones(3)
             W2: UPTRI(W1)

             W2 == {{1, 1, 1},
                    {0, 1, 1},
                    {0, 0, 1}}


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

    See Also:
             Colnos
             Lotri
             Lotrix
             Rownos
             Uptrix

#endif

/*
 *  UPTRI returns the upper triangle of a matrix, including the main
 *  diagnonal, with the lower triangle zeroed out.
 */

uptri(M)
{
        return((M)*(rownos(M) <= colnos(M)));
}