template <class ZT, class FT> void MatHouseholder<ZT, FT>::swap(int i, int j)
{
FPLLL_DEBUG_CHECK(0 <= i && i < j && j < d);
// Invalidate to the min not modified row, that is i
invalidate_row(i);
b.swap_rows(i, j);
bf.swap_rows(i, j);
iter_swap(sigma.begin() + i, sigma.begin() + j);
if (enable_row_expo)
iter_swap(row_expo.begin() + i, row_expo.begin() + j);
iter_swap(init_row_size.begin() + i, init_row_size.begin() + j);
iter_swap(R_history.begin() + i, R_history.begin() + j);
if (enable_transform)
{
u.swap_rows(i, j);
if (enable_inverse_transform)
u_inv_t.swap_rows(i, j);
}
iter_swap(norm_square_b.begin() + i, norm_square_b.begin() + j);
iter_swap(expo_norm_square_b.begin() + i, expo_norm_square_b.begin() + j);
#ifdef DEBUG
iter_swap(col_kept.begin() + i, col_kept.begin() + j);
#endif // DEBUG
}
void menu::invalidate_row_pos(size_t pos)
{
if(pos >= items_.size()) {
return;
}
invalidate_row(items_[pos].id);
}
bool MatHouseholder<ZT, FT>::size_reduce(int k, int size_reduction_end, int size_reduction_start)
{
FPLLL_DEBUG_CHECK(k > 0 && k < d);
bool reduced = false;
for (int i = size_reduction_end - 1; i >= size_reduction_start; i--)
{
// R(k, i) / R(i, i) = ftmp1 * 2^(row_expo[k] - row_expo[i])
#ifndef HOUSEHOLDER_PRECOMPUTE_INVERSE
ftmp1.div(R(k, i), R(i, i));
#else // HOUSEHOLDER_PRECOMPUTE_INVERSE
ftmp1.mul(R(k, i), R_inverse_diag[i]);
#endif // HOUSEHOLDER_PRECOMPUTE_INVERSE
/* If T = mpfr or dpe, enable_row_expo must be false and then, expo1 - expo0 == 0 (required by
* rnd_we with these types) */
// rnd(R(k, i) / R(i, i)) = ftmp1 * 2^(row_expo[k] - row_expo[i])
ftmp1.rnd_we(ftmp1, row_expo[k] - row_expo[i]);
// ftmp1 * 2^(expo1 - expo0) is equal to -X[i] in Algorithm 3 of [MSV, ISSAC'09]
ftmp1.neg(ftmp1);
if (ftmp1.sgn() != 0) // Equivalent to test if ftmp1 == 0
{
// b[k] will be reduced by ftmp1 * 2^(row_expo[k] - row_expo[i]) * b[i]
row_addmul_we(k, i, ftmp1, row_expo[k] - row_expo[i]);
// b[k] was reduced
reduced = true;
}
}
// b[k] was reduced by at least one b[i]
if (reduced)
{
#ifdef DEBUG
// b[k] has changed
col_kept[k] = false;
#endif // DEBUG
// Invalidate since b has changed, but R is not recomputed. We do operations on R[k], but not
// the one to get the correct R[k]: the operations are the one mentionned in line 5 of
// Algorithm 3 [MSV, ISSAC'09].
invalidate_row(k);
}
return reduced;
}
