/** @param array $set [ varname => fraction ] */
function __construct(array $set)
{
foreach ($set as $var => $coeff) {
$set[$var] = Fraction::create($coeff);
}
ksort($set);
$this->set = $set;
}
/**
* @param string $var
* @param array $set
* @param Fraction|numeric $b
*/
function __construct($var, array $set, $b)
{
parent::__construct($set);
$this->var = (string) $var;
$this->b = Fraction::create($b);
}
/**
* @param array $set
* @param Fraction|numeric $value
*/
function __construct(array $set, $value)
{
parent::__construct($set);
$this->value = Fraction::create($value);
}
/**
* @param array $set
* @param int $type
* @param Fraction|numeric $limit
*/
function __construct(array $set, $type, $limit)
{
parent::__construct($set);
$this->type = (int) $type;
$this->limit = Fraction::create($limit);
}
/** @return Table */
function nextStep()
{
if ($this->z2 !== NULL && !$this->hasHelperInBasis()) {
$this->removeHelpers();
}
$newrows = array();
$keycol = $this->getKeyColumn();
$keyrow = $this->getKeyRow();
if ($keycol === NULL || $keyrow === NULL) {
return $this;
}
foreach ($this->rows as $row) {
$rowset = array();
if ($row->getVar() === $keyrow->getVar()) {
$var = $keycol;
$b = $row->getB()->divide($keyrow->get($keycol));
foreach ($row->getSet() as $v => $c) {
$rowset[$v] = $c->divide($keyrow->get($keycol));
}
} else {
$var = $row->getVar();
$set = $row->getSet();
$dvd = $set[$keycol]->multiply(-1)->divide($keyrow->get($keycol));
$b = $dvd->multiply($keyrow->getB())->add($row->getB());
foreach ($row->getSet() as $v => $c) {
$rowset[$v] = $dvd->multiply($keyrow->get($v))->add($c);
}
}
$newrows[$var] = array($rowset, $b);
}
$this->rows = array();
foreach ($newrows as $var => $meta) {
$this->addRow(new TableRow($var, $meta[0], $meta[1]));
}
foreach (array('z', 'z2') as $zvar) {
if ($this->{$zvar} === NULL) {
continue;
}
$zcoeffs = array();
$zdvd = $this->{$zvar}->get($keycol)->multiply(-1)->divide($keyrow->get($keycol));
foreach ($this->{$zvar}->getSet() as $v => $c) {
$zcoeffs[$v] = $zdvd->multiply($keyrow->get($v))->add($c);
}
$this->{$zvar} = new TableRow($zvar, $zcoeffs, $zdvd->multiply($keyrow->getB())->add($this->{$zvar}->getB()));
}
// find solution (if any)
if ($this->isSolved()) {
if ($this->solution !== FALSE) {
$this->solution = array();
foreach ($this->z->getVariableList() as $var) {
if (strncmp($var, 'y', 1) === 0) {
continue;
}
foreach ($this->rows as $row) {
if ($row->getVar() === $var) {
$this->solution[$var] = $row->getB();
continue 2;
}
}
$this->solution[$var] = Fraction::create(0);
}
ksort($this->solution);
}
}
return $this;
}
/** @return Table */
function toTable()
{
$zcoeffs = array();
foreach ($this->function->getSet() as $var => $coeff) {
$zcoeffs[$var] = $coeff->multiply(-1);
}
$z = new ValueFunc($zcoeffs, 0);
$z2b = Fraction::create(0);
$z2coeffs = array();
foreach ($this->restrictions as $idx => $r) {
foreach ($r->getSet() as $var => $coeff) {
if (strncmp($var, 'y', 1) === 0 && $coeff->isEqualTo(1)) {
foreach ($r->getSet() as $v => $c) {
!isset($z2coeffs[$v]) && ($z2coeffs[$v] = Fraction::create(0));
strncmp($v, 'y', 1) !== 0 && ($z2coeffs[$v] = $z2coeffs[$v]->subtract($c));
}
$z2b = $z2b->subtract($r->getLimit());
}
}
}
$z2 = count($z2coeffs) ? new ValueFunc($z2coeffs, $z2b) : NULL;
$table = new Table($z, $z2);
foreach ($this->basismap as $var => $idx) {
$table->addRow(new TableRow($var, $this->restrictions[$idx]->getSet(), $this->restrictions[$idx]->getLimit()));
}
return $table;
}
