/**
* Converts a DirectedGraph into a DirectedAcyclicGraph.
*
* A DirectedGraph can be converted into a DirectedAcyclicGraph when
* is does not contain any cycle.
*
* @param \GraphAPI\Component\Graph\DirectedGraph $g
* @param type $ignore_exception
* @throws \GraphAPI\Component\Graph\Exception
*/
static function fromDirectedGraph(DirectedGraph $g, $ignore_exception = FALSE)
{
$d = new DirectedAcyclicGraph();
foreach ($g->getNodeIds() as $id) {
$links = $g->getLinks($id);
foreach ($links as $link) {
try {
$d->addLink($id, $link);
} catch (\Exception $exc) {
if (!$ignore_exception) {
throw $exc;
}
}
}
}
return $d;
}
function dumpTSL(DirectedAcyclicGraph $g)
{
echo "\nTSL: " . join(',', $g->getTSL()) . "\n";
}