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#include "reversesearch.h"
#include "buchberger.h"
#include "wallideal.h"
#include "printer.h"
#include "lp.h"
#include "log.h"
bool ReverseSearch::computeSearchEdge(PolynomialSet &groebnerBasis, IntegerVector *edge)
{
// fprintf(Stderr,"Computing search edge..");
IntegerVectorList normals=wallInequalities(groebnerBasis);
normals.sort(LexicographicTermOrder());// Is this needed to make the interior point computation deterministic?
// fprintf(Stderr,"\nBasis with no interior point:\n");
// AsciiPrinter(Stderr).printPolynomialSet(groebnerBasis);
if(normals.empty())
{
log3 fprintf(Stderr,"WARNING: reversesearch.cpp - No normals\n");
}
IntegerVectorList::const_iterator r=shootRay(normals);
// fprintf(Stderr,"..done\n");
if(r!=normals.end())
{
*edge=*r;
return true;
}
return false;
/*
IntegerVectorList normals=wallNormals(groebnerBasis);
normals.sort(LexicographicTermOrder());
for(IntegerVectorList::const_iterator i=normals.begin();i!=normals.end();i++)
if(termOrder(*i,*i-*i))
if(isFacet(normals,i))
if(wallContainsPositiveVector(*i))
{
*edge=*i;
return true;
}
return false;
*/
}
/*void ReverseSearch::setProgressPrinting(bool p)
{
progressPrinting=p;
}
*/
static int depth;
//int ReverseSearch::treeSize(const PolynomialSet &groebnerBasis)
int ReverseSearch::treeSize(PolynomialSet &groebnerBasis)
{
PolynomialRing theRing=groebnerBasis.getRing();
depth++;
// if(progressPrinting)
{
static int n;
n++;
if(!(n%10))
log2 fprintf(Stderr,"%i %i\n",n,depth);
}
int s=1;
if(!targetBasis(groebnerBasis)){broken=true;return s;}
IntegerVectorList flipable;
// fprintf(Stderr,"Number of flipable facets:%i\n",flipable.size());
if(1)
{
// fprintf(Stderr,"isKnownToBeHomogeneous:%i\n",isKnownToBeHomogeneous);
// fprintf(Stderr,"Start finding flipable\n");
flipable=wallFlipableNormals(groebnerBasis,isKnownToBeHomogeneous);
// fprintf(Stderr,"done\n");
}
else
{
// For non-homogeneous ideals the following test does not work since it also findes facets that do not intersect the positive orthant.
assert(isKnownToBeHomogeneous);
//Taken from Breadth-first search. Apparently this is faster..
IntegerVectorList normals=algebraicTest(wallInequalities(groebnerBasis),groebnerBasis);
// fprintf(Stderr,"Number of inequalities:%i\n",normals.size());
// AsciiPrinter(Stderr).printVectorList(normals);
for(IntegerVectorList::iterator i=normals.begin();i!=normals.end();i++)
{
if(!termOrder(*i,*i-*i))
{
// AsciiPrinter(Stderr).printVector(*i);
if(isFacet(normals,i))
{
// fprintf(Stderr,"isFACET!n");
if(wallContainsPositiveVector(*i))
flipable.push_back(*i);
}
else
{
IntegerVectorList::iterator temp=i;
temp++;
normals.erase(i);
temp--;
i=temp;
}
}
}
}
// AsciiPrinter(Stderr).printVectorList(flipable);
// fprintf(Stderr,"Number of flipable facets:%i\n",flipable.size());
for(IntegerVectorList::iterator i=flipable.begin();i!=flipable.end();i++)
{
if(!termOrder(*i,*i-*i))
{
PolynomialSet neighbour=flip(groebnerBasis,*i);
IntegerVector edge;
if(computeSearchEdge(neighbour,&edge))
if(dependent(edge,*i))
{
groebnerBasis=PolynomialSet(theRing);//forget current
s+=treeSize(neighbour);
groebnerBasis=flip(neighbour,edge);//recall
if(broken)return s;
}
}
}
depth--;
return s;
}
PolynomialSet ReverseSearch::findRoot(PolynomialSet groebnerBasis)
{
log2 fprintf(Stderr,"Computing root\n");
log2 buchberger(&groebnerBasis,termOrder);
IntegerVector edge;
while(computeSearchEdge(groebnerBasis,&edge))
{
log2 AsciiPrinter(Stderr).printVector(edge);
groebnerBasis=flip(groebnerBasis,edge);
}
log2 fprintf(Stderr,"Done computing root\n");
return groebnerBasis;
}
ReverseSearch::ReverseSearch(const TermOrder &termOrder_):
numberOfVertices(0),
numberOfEdges(0),
termOrder(termOrder_),
isKnownToBeHomogeneous(false)//,
// progressPrinting(false)
{
}
void ReverseSearch::enumerate(const PolynomialSet &groebnerBasis)
{
broken=false;
PolynomialSet root=findRoot(groebnerBasis);
if(!isKnownToBeHomogeneous)isKnownToBeHomogeneous=isIdealHomogeneous(root);
// fprintf(Stderr,"HOMOGENEOUS:%i\n",isKnownToBeHomogeneous);
targetBeginEnumeration(groebnerBasis);
numberOfVertices=treeSize(root);
targetEndEnumeration();
// fprintf(Stderr,"numberOfVertices:%i\n",numberOfVertices);
}
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