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debugging diff logic simple simplex

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2014-03-04 21:19:29 -08:00
parent c4b1f5c30e
commit fe61492d5d
3 changed files with 109 additions and 74 deletions
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41
src/math/simplex/simplex_def.h
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@ -608,6 +608,7 @@ namespace simplex {
// optimal
return l_true;
}
TRACE("simplex", tout << "x_i: v" << x_i << " x_j: v" << x_j << "\n";);
var_info& vj = m_vars[x_j];
if (x_i == null_var) {
if (inc && vj.m_upper_valid) {
@ -635,8 +636,9 @@ namespace simplex {
//
pivot(x_i, x_j, a_ij);
move_to_bound(x_i, inc == m.is_pos(a_ij));
move_to_bound(x_i, inc != m.is_pos(a_ij));
SASSERT(well_formed_row(row(m_vars[x_j].m_base2row)));
TRACE("simplex", display(tout););
}
return l_true;
}
@ -651,22 +653,37 @@ namespace simplex {
else {
em.sub(vi.m_upper, vi.m_value, delta);
}
TRACE("simplex", tout << "move " << (to_lower?"to_lower":"to_upper")
<< " v" << x << " " << em.to_string(delta) << "\n";);
col_iterator it = M.col_begin(x), end = M.col_end(x);
for (; it != end && is_pos(delta); ++it) {
//
// base_coeff*s + coeff*x + R = 0
//
// to_lower coeff > 0 base_coeff > 0 bound(s)
// ------------------------------------------------------
// T T T !to_lower
// T T F to_lower
// T F T to_lower
// T F F !to_lower
//
var_t s = m_row2base[it.get_row().id()];
var_info& vs = m_vars[s];
numeral const& coeff = it.get_row_entry().m_coeff;
numeral const& base_coeff = vs.m_base_coeff;
SASSERT(!m.is_zero(coeff));
bool inc_s = (m.is_pos(coeff) == to_lower);
bool base_to_lower = (m.is_pos(coeff) != m.is_pos(base_coeff)) == to_lower;
eps_numeral const* bound = 0;
if (inc_s && vs.m_upper_valid) {
if (!base_to_lower && vs.m_upper_valid) {
bound = &vs.m_upper;
}
else if (!inc_s && vs.m_lower_valid) {
else if (base_to_lower && vs.m_lower_valid) {
bound = &vs.m_lower;
}
if (bound) {
// |delta2*coeff| = |(bound-value)*base_coeff|
em.sub(*bound, vs.m_value, delta2);
em.mul(delta2, base_coeff, delta2);
em.div(delta2, coeff, delta2);
abs(delta2);
if (delta2 < delta) {
@ -694,8 +711,11 @@ namespace simplex {
for (; it != end; ++it) {
var_t x = it->m_var;
if (x == v) continue;
bool is_pos = m.is_pos(it->m_coeff);
bool is_pos = m.is_pos(it->m_coeff) == m.is_pos(m_vars[v].m_base_coeff);
if ((is_pos && at_upper(x)) || (!is_pos && at_lower(x))) {
TRACE("simplex", tout << "v" << x << " pos: " << is_pos
<< " at upper: " << at_upper(x)
<< " at lower: " << at_lower(x) << "\n";);
continue; // variable cannot be used for improving bounds.
// TBD check?
}
@ -737,7 +757,11 @@ namespace simplex {
var_info& vi = m_vars[s];
numeral const& a_ij = it.get_row_entry().m_coeff;
numeral const& a_ii = vi.m_base_coeff;
bool inc_s = m.is_neg(a_ij) ? inc : !inc;
bool inc_s = (m.is_pos(a_ii) != m.is_pos(a_ij)) ? inc : !inc;
TRACE("simplex", tout << "v" << x_j << " incs: " << inc_s
<< " upper valid:" << vi.m_upper_valid
<< " lower valid:" << vi.m_lower_valid << "\n";
display_row(tout, r););
if ((inc_s && !vi.m_upper_valid) || (!inc_s && !vi.m_lower_valid)) {
continue;
}
@ -751,14 +775,15 @@ namespace simplex {
if (is_neg(curr_gain)) {
curr_gain.neg();
}
if (x_i == null_var || (curr_gain < gain) ||
if (x_i == null_var || (gain < curr_gain) ||
(is_zero(gain) && is_zero(curr_gain) && s < x_i)) {
x_i = s;
gain = curr_gain;
new_a_ij = a_ij;
TRACE("simplex", tout << "x_j v" << x_j << " x_i v" << x_i << " gain: ";
tout << em.to_string(curr_gain) << "\n";);
}
}
TRACE("simplex", tout << "x_i v" << x_i << "\n";);
return x_i;
}