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/*
Copyright (C) 2011 Fredrik Johansson
This file is part of FLINT.
FLINT is free software: you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License (LGPL) as published
by the Free Software Foundation; either version 3 of the License, or
(at your option) any later version. See <https://www.gnu.org/licenses/>.
*/
#include "fmpq.h"
#include "fmpq_mat.h"
void fmpq_mat_mul_direct(fmpq_mat_t C, const fmpq_mat_t A, const fmpq_mat_t B)
{
slong i, j, k;
if (A == C || B == C)
{
flint_throw(FLINT_ERROR, "Exception (fmpq_mat_mul_direct). Aliasing not implemented.\n");
}
if (A->c == 0)
{
fmpq_mat_zero(C);
return;
}
for (i = 0; i < A->r; i++)
{
for (j = 0; j < B->c; j++)
{
fmpq_mul(fmpq_mat_entry(C, i, j),
fmpq_mat_entry(A, i, 0),
fmpq_mat_entry(B, 0, j));
for (k = 1; k < A->c; k++)
{
fmpq_addmul(fmpq_mat_entry(C, i, j),
fmpq_mat_entry(A, i, k),
fmpq_mat_entry(B, k, j));
}
}
}
}