1 /*
2     Copyright (C) 2011 Fredrik Johansson
3 
4     This file is part of FLINT.
5 
6     FLINT is free software: you can redistribute it and/or modify it under
7     the terms of the GNU Lesser General Public License (LGPL) as published
8     by the Free Software Foundation; either version 2.1 of the License, or
9     (at your option) any later version.  See <https://www.gnu.org/licenses/>.
10 */
11 
12 #include "flint.h"
13 #include "nmod_poly.h"
14 #include "nmod_poly_mat.h"
15 
16 int
nmod_poly_mat_is_one(const nmod_poly_mat_t A)17 nmod_poly_mat_is_one(const nmod_poly_mat_t A)
18 {
19     slong i, j;
20 
21     if (A->r == 0 || A->c == 0)
22         return 1;
23 
24     for (i = 0; i < A->r; i++)
25     {
26         for (j = 0; j < A->c; j++)
27         {
28             if (i == j)
29             {
30                 if (!nmod_poly_is_one(nmod_poly_mat_entry(A, i, j)))
31                     return 0;
32             }
33             else
34             {
35                 if (!nmod_poly_is_zero(nmod_poly_mat_entry(A, i, j)))
36                     return 0;
37             }
38         }
39     }
40 
41     return 1;
42 }
43