53 lines
1.6 KiB
C
53 lines
1.6 KiB
C
/*=============================================================================
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This file is part of FLINT.
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FLINT is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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FLINT is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with FLINT; if not, write to the Free Software
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Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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=============================================================================*/
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/******************************************************************************
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Copyright (C) 2010 Fredrik Johansson
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******************************************************************************/
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#include <stdio.h>
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#include "flint.h"
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#include "ulong_extras.h"
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#include "nmod_mat.h"
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#include "nmod_vec.h"
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void
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nmod_mat_randrank(nmod_mat_t mat, flint_rand_t state, slong rank)
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{
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slong i;
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mp_limb_t * diag;
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if (rank < 0 || rank > mat->r || rank > mat->c)
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{
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flint_printf("Exception (nmod_mat_randrank). Impossible rank.\n");
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abort();
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}
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diag = _nmod_vec_init(rank);
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for (i = 0; i < rank; i++)
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diag[i] = 1 + n_randint(state, mat->mod.n - 1);
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nmod_mat_randpermdiag(mat, state, diag, rank);
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_nmod_vec_clear(diag);
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}
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