mirror of
https://github.com/vale981/arb
synced 2025-03-05 09:21:38 -05:00
73 lines
1.5 KiB
C
73 lines
1.5 KiB
C
/*
|
|
Copyright (C) 2012 Fredrik Johansson
|
|
|
|
This file is part of Arb.
|
|
|
|
Arb 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 2.1 of the License, or
|
|
(at your option) any later version. See <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include "acb_mat.h"
|
|
|
|
int
|
|
acb_mat_lu(slong * P, acb_mat_t LU, const acb_mat_t A, slong prec)
|
|
{
|
|
acb_t d, e;
|
|
acb_ptr * a;
|
|
slong i, j, m, n, r, row, col;
|
|
int result;
|
|
|
|
if (acb_mat_is_empty(A))
|
|
return 1;
|
|
|
|
m = acb_mat_nrows(A);
|
|
n = acb_mat_ncols(A);
|
|
|
|
acb_mat_set(LU, A);
|
|
|
|
a = LU->rows;
|
|
|
|
row = col = 0;
|
|
for (i = 0; i < m; i++)
|
|
P[i] = i;
|
|
|
|
acb_init(d);
|
|
acb_init(e);
|
|
|
|
result = 1;
|
|
|
|
while (row < m && col < n)
|
|
{
|
|
r = acb_mat_find_pivot_partial(LU, row, m, col);
|
|
|
|
if (r == -1)
|
|
{
|
|
result = 0;
|
|
break;
|
|
}
|
|
else if (r != row)
|
|
acb_mat_swap_rows(LU, P, row, r);
|
|
|
|
acb_set(d, a[row] + col);
|
|
|
|
for (j = row + 1; j < m; j++)
|
|
{
|
|
acb_div(e, a[j] + col, d, prec);
|
|
acb_neg(e, e);
|
|
_acb_vec_scalar_addmul(a[j] + col,
|
|
a[row] + col, n - col, e, prec);
|
|
acb_zero(a[j] + col);
|
|
acb_neg(a[j] + row, e);
|
|
}
|
|
|
|
row++;
|
|
col++;
|
|
}
|
|
|
|
acb_clear(d);
|
|
acb_clear(e);
|
|
|
|
return result;
|
|
}
|