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working on stand-alone simplex

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2014-01-26 20:25:36 -08:00
parent c14c65465a
commit 363af825c0
4 changed files with 32 additions and 6 deletions
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16
src/math/simplex/simplex_def.h
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@ -29,9 +29,13 @@ namespace simplex {
for (unsigned i = 0; !found && i < num_vars; ++i) found = vars[i] == base;
SASSERT(found);
);
scoped_numeral base_coeff(m);
row r = M.mk_row();
for (unsigned i = 0; i < num_vars; ++i) {
M.add(r, coeffs[i], vars[i]);
if (vars[i] == base) {
m.set(base_coeff, coeffs[i]);
}
}
while (m_row2base.size() <= r.id()) {
m_row2base.push_back(null_var);
@ -39,6 +43,7 @@ namespace simplex {
m_row2base[r.id()] = base;
m_vars[base].m_base2row = r.id();
m_vars[base].m_is_base = true;
m.set(m_vars[base].m_base_coeff, base_coeff);
return r;
}
@ -54,7 +59,8 @@ namespace simplex {
var_info& vi = m_vars[var];
em.set(vi.m_lower, b);
vi.m_lower_valid = true;
if (em.lt(vi.m_value, b)) {
SASSERT(!vi.m_upper_valid || em.le(b, vi.m_upper));
if (!vi.m_is_base && em.lt(vi.m_value, b)) {
scoped_eps_numeral delta(em);
em.sub(b, vi.m_value, delta);
update_value(var, delta);
@ -66,7 +72,8 @@ namespace simplex {
var_info& vi = m_vars[var];
em.set(vi.m_upper, b);
vi.m_upper_valid = true;
if (em.gt(vi.m_value, b)) {
SASSERT(!vi.m_lower_valid || em.le(vi.m_lower, b));
if (!vi.m_is_base && em.gt(vi.m_value, b)) {
scoped_eps_numeral delta(em);
em.sub(b, vi.m_value, delta);
update_value(var, delta);
@ -102,13 +109,13 @@ namespace simplex {
for (unsigned i = 0; i < m_vars.size(); ++i) {
var_info const& vi = m_vars[i];
out << "v" << i << " ";
if (vi.m_is_base) out << "b:" << vi.m_base2row << " ";
out << em.to_string(vi.m_value);
out << " [";
if (vi.m_lower_valid) out << em.to_string(vi.m_lower); else out << "-oo";
out << ":";
if (vi.m_upper_valid) out << em.to_string(vi.m_upper); else out << "oo";
out << "]";
if (vi.m_is_base) out << " b:" << vi.m_base2row;
out << "\n";
}
}
@ -176,8 +183,9 @@ namespace simplex {
var_info& x_iI = m_vars[x_i];
var_info& x_jI = m_vars[x_j];
unsigned r_i = x_iI.m_base2row;
x_jI.m_base2row = r_i;
m_row2base[r_i] = x_j;
x_jI.m_base2row = r_i;
m.set(x_jI.m_base_coeff, a_ij);
x_jI.m_is_base = true;
x_iI.m_is_base = false;
if (outside_bounds(x_j)) {