interval/test/det.cpp
2006-02-02 12:35:58 +00:00

104 lines
2.6 KiB
C++

/* Boost test/det.cpp
* test protected and unprotected rounding on an unstable determinant
*
* Copyright 2002-2003 Guillaume Melquiond
*
* Distributed under the Boost Software License, Version 1.0.
* (See accompanying file LICENSE_1_0.txt or
* copy at http://www.boost.org/LICENSE_1_0.txt)
*/
#include <boost/numeric/interval.hpp>
#include <boost/test/minimal.hpp>
#include "bugs.hpp"
#define size 8
template<class I>
void det(I (&mat)[size][size]) {
for(int i = 0; i < size; i++)
for(int j = 0; j < size; j++)
mat[i][j] = I(1) / I(i + j + 1);
for(int i = 0; i < size - 1; i++) {
int m = i, n = i;
typename I::base_type v = 0;
for(int a = i; a < size; a++)
for(int b = i; b < size; b++) {
typename I::base_type w = abs(mat[a][b]).lower();
if (w > v) { m = a; n = b; v = w; }
}
if (n != i)
for(int a = 0; a < size; a++) {
I t = mat[a][n];
mat[a][n] = mat[a][i];
mat[a][i] = t;
}
if (m != i)
for(int b = i; b < size; b++) {
I t = mat[m][b];
mat[m][b] = mat[m][i];
mat[m][i] = t;
}
if (((m + n) & 1) == 1) { };
I c = mat[i][i];
for(int j = i + 1; j < size; j++) {
I f = mat[j][i] / c;
for(int k = i; k < size; k++)
mat[j][k] -= f * mat[i][k];
}
if (zero_in(c)) return;
}
}
namespace my_namespace {
using namespace boost;
using namespace numeric;
using namespace interval_lib;
template<class T>
struct variants {
typedef interval<T> I_op;
typedef typename change_rounding<I_op, save_state<rounded_arith_std<T> > >::type I_sp;
typedef typename unprotect<I_op>::type I_ou;
typedef typename unprotect<I_sp>::type I_su;
typedef T type;
};
}
template<class T>
bool test() {
typedef my_namespace::variants<double> types;
types::I_op mat_op[size][size];
types::I_sp mat_sp[size][size];
types::I_ou mat_ou[size][size];
types::I_su mat_su[size][size];
det(mat_op);
det(mat_sp);
{ types::I_op::traits_type::rounding rnd; det(mat_ou); }
{ types::I_sp::traits_type::rounding rnd; det(mat_su); }
for(int i = 0; i < size; i++)
for(int j = 0; j < size; j++) {
typedef types::I_op I;
I d_op = mat_op[i][j];
I d_sp = mat_sp[i][j];
I d_ou = mat_ou[i][j];
I d_su = mat_su[i][j];
if (!(equal(d_op, d_sp) && equal(d_sp, d_ou) && equal(d_ou, d_su)))
return false;
}
return true;
}
int test_main(int, char *[]) {
BOOST_CHECK(test<float>());
BOOST_CHECK(test<double>());
BOOST_CHECK(test<long double>());
# ifdef __BORLANDC__
::detail::ignore_warnings();
# endif
return 0;
}