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merging with the lp fork

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Signed-off-by: Lev Nachmanson <levnach@hotmail.com>
This commit is contained in:
Lev Nachmanson 2017-05-10 16:53:25 -07:00
parent cf695ab876
commit b08f094620
44 changed files with 902 additions and 319 deletions
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96
src/util/lp/permutation_matrix.hpp
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@ -320,100 +320,4 @@ template <typename T, typename X> bool permutation_matrix<T, X>::is_identity() c
}
#ifdef LEAN_DEBUG
template <typename T, typename X>
permutation_generator<T, X>::permutation_generator(unsigned n): m_n(n), m_current(n) {
lean_assert(n > 0);
if (n > 1) {
m_lower = new permutation_generator(n - 1);
} else {
m_lower = nullptr;
}
m_last = 0;
}
template <typename T, typename X>
permutation_generator<T, X>::permutation_generator(const permutation_generator & o): m_n(o.m_n), m_done(o.m_done), m_current(o.m_current), m_last(o.m_last) {
if (m_lower != nullptr) {
m_lower = new permutation_generator(o.m_lower);
} else {
m_lower = nullptr;
}
}
template <typename T, typename X> bool
permutation_generator<T, X>::move_next() {
if (m_done) {
return false;
}
if (m_lower == nullptr) {
if (m_last == 0) {
m_last++;
return true;
} else {
m_done = true;
return false;
}
} else {
if (m_last < m_n && m_last > 0) {
m_current[m_last - 1] = m_current[m_last];
m_current[m_last] = m_n - 1;
m_last++;
return true;
} else {
if (m_lower -> move_next()) {
auto lower_curr = m_lower -> current();
for ( unsigned i = 1; i < m_n; i++ ){
m_current[i] = (*lower_curr)[i - 1];
}
m_current[0] = m_n - 1;
m_last = 1;
return true;
} else {
m_done = true;
return false;
}
}
}
}
template <typename T, typename X>
inline unsigned number_of_inversions(permutation_matrix<T, X> & p) {
unsigned ret = 0;
unsigned n = p.size();
for (unsigned i = 0; i < n; i++) {
for (unsigned j = i + 1; j < n; j++) {
if (p[i] > p[j]) {
ret++;
}
}
}
return ret;
}
template <typename T, typename X>
T det_val_on_perm(permutation_matrix<T, X>* u, const matrix<T, X>& m) {
unsigned n = m.row_count();
T ret = numeric_traits<T>::one();
for (unsigned i = 0; i < n; i++) {
unsigned j = (*u)[i];
ret *= m(i, j);
}
return ret * sign(*u);
}
template <typename T, typename X>
T determinant(const matrix<T, X>& m) {
lean_assert(m.column_count() == m.row_count());
unsigned n = m.row_count();
permutation_generator<T, X> allp(n);
T ret = numeric_traits<T>::zero();
while (allp.move_next()){
ret += det_val_on_perm(allp.current(), m);
}
return ret;
}
#endif
}