/* +---------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)               |
   |                          https://www.mrpt.org/                            |
   |                                                                           |
   | Copyright (c) 2005-2021, Individual contributors, see AUTHORS file        |
   | See: https://www.mrpt.org/Authors - All rights reserved.                  |
   | Released under BSD License. See details in https://www.mrpt.org/License   |
   +---------------------------------------------------------------------------+ */
#include "cs.h"
/* pinv = p', or p = pinv' */
int *cs_pinv (int const *p, int n)
{
    int k, *pinv ;
    if (!p) return (NULL) ;                     /* p = NULL denotes identity */
    pinv = cs_malloc (n, sizeof (int)) ;        /* allocate result */
    if (!pinv) return (NULL) ;                  /* out of memory */
    for (k = 0 ; k < n ; k++) pinv [p [k]] = k ;/* invert the permutation */
    return (pinv) ;                             /* return result */
}
