Changeset 86f23e in git

Timestamp:

Apr 30, 2009, 11:32:01 AM (15 years ago)

Author:

Martin Monerjan

Branches:

(u'spielwiese', 'fe61d9c35bf7c61f2b6cbf1b56e25e2f08d536cc')

Children:

fca87ac65d9188c296070cf81e3cdbe571886b62

Parents:

d7fe2a25f82c1fea9eea86260f9312234f364449

Message:

populated method revereSearch
new method isSearchFacet; calling with references does not work as expected though
rev will not compile


git-svn-id: file:///usr/local/Singular/svn/trunk@11760 2c84dea3-7e68-4137-9b89-c4e89433aadc

File:

• kernel/gfan.cc (modified) (5 diffs)

kernel/gfan.cc

@@ -2 +2 @@
 Compute the Groebner fan of an ideal
 $Author: monerjan $
-$Date: 2009-04-29 07:22:48 $
-$Header: /exports/cvsroot-2/cvsroot/kernel/gfan.cc,v 1.42 2009-04-29 07:22:48 monerjan Exp $
-$Id: gfan.cc,v 1.42 2009-04-29 07:22:48 monerjan Exp $
+$Date: 2009-04-30 09:32:01 $
+$Header: /exports/cvsroot-2/cvsroot/kernel/gfan.cc,v 1.43 2009-04-30 09:32:01 monerjan Exp $
+$Id: gfan.cc,v 1.43 2009-04-30 09:32:01 monerjan Exp $
 */
 
@@ -228 +228 @@
                 }
                 
-                void getIntPoint()
+                /** \brief Return the interior point */
+                intvec *getIntPoint()
+                {
+                        return this->ivIntPt;
+                }
+                
+                void showIntPoint()
                 {
                         ivIntPt->show();
@@ -1014 +1020 @@
                 }//rCopyAndChange
                 
-                void reverseSearch()
-                {
+                /** 
+                * Determines whether a given facet of a cone is the search facet of a neighbouring cone
+                *
+                */
+                bool isSearchFacet(gcone &tmpcone, facet *testfacet)
+                {                       
+                        ring actRing=currRing;
+                        
+                        facet *fMin=new facet();        //Pointer to the "minimal" facet
+                        facet *fAct;
+                        fMin = testfacet;
+                        fAct = fMin;
+                        
+                        rChangeCurrRing(this->rootRing);
+                        poly p=NULL;
+                        poly q=NULL;
+                        intvec *p_weight = new intvec(this->numVars);                   
+                        intvec *q_weight = new intvec(this->numVars);
+                        intvec *sigma = new intvec(this->numVars);
+                        sigma=tmpcone.getIntPoint();
+                        int *u=(int *)omAlloc((this->numVars+1)*sizeof(int));
+                        int *v=(int *)omAlloc((this->numVars+1)*sizeof(int));
+                        int weight1,weight2;
+                        while(tmpcone.facetPtr->next!=NULL)
+                        {
+                                /* Get alpha_i and alpha_{i+1} */
+                                p_weight=fMin->getFacetNormal();
+                                q_weight=fMin->next->getFacetNormal();
+                                
+                                /*Compute the dot product of sigma and alpha_{i,j}*/
+                                weight1=dotProduct(sigma,p_weight);
+                                weight2=dotProduct(sigma,q_weight);
+                                
+                                /*Adjust alpha_i and alpha_i+1 accordingly*/
+                                for(int ii=1;ii<=this->numVars;ii++)
+                                {
+                                        /*p_weight[ii]=weight1*(*p_weight)[ii];
+                                        q_weight[ii]=weight2*(*q_weight)[ii];*/
+                                        u[ii]=weight1*(*p_weight)[ii];
+                                        v[ii]=weight2*(*q_weight)[ii];
+                                }
+                                
+                                /*Now p_weight and q_weight need to be compared as exponent vectors*/
+                                pSetExpV(p,u);
+                                pSetExpV(q,v);
+                                /*We want to check whether x^p < x^q 
+                                => want to check for return value 1 */
+                                if (pLmCmp(p,q)==1)     //i.e. x^q is smaller
+                                {
+                                        fMin=fMin->next;
+                                        fAct=fMin;
+                                }
+                                else
+                                {
+                                        fAct=fAct->next;
+                                }
+                        }//while(tmpcone.facetPtr->next!=NULL)
+                        rChangeCurrRing(actRing);
+                }//bool isSearchFacet
+                
+                void reverseSearch(gcone gcAct) //no const possible here since we call gcAct->flip
+                {
+                        facet *fAct=new facet();
+                        fAct = gcAct.facetPtr;                  
+                        
+                        while(fAct->next!=NULL)
+                        {
+                                gcAct.flip(gcAct.gcBasis,gcAct.facetPtr);
+                                gcone *gcTmp = new gcone(gcAct);
+                                idShow(gcTmp->gcBasis);
+                                gcTmp->getConeNormals(gcTmp->gcBasis, TRUE);
+                                gcTmp->showIntPoint();
+                                /*recursive part goes gere*/
+                                if (isSearchFacet(gcTmp,gcAct.facetPtr))
+                                {
+                                        gcAct.next=gcTmp;
+                                        reverseSearch(*gcTmp);
+                                }
+                                else
+                                {
+                                        delete gcTmp;
+                                        /*NOTE remove fAct from linked list. It's no longer needed*/
+                                }
+                                /*recursion ends*/
+                                fAct = fAct->next;              
+                        }//while(fAct->next!=NULL)
                 }//reverseSearch
 };//class gcone
@@ -1078 +1168 @@
         NOTE: Check for flippability is not very sophisticated
         */
-        facet *fAct=new facet();
+        /*facet *fAct=new facet();
         fAct=gcAct->facetPtr;
         while(fAct->next!=NULL)
@@ -1088 +1178 @@
                 gcTmp->getIntPoint();
                 fAct = fAct->next;              
-        }
-        
+        }*/
+        gcAct->reverseSearch(*gcAct);
         /*As of now extra.cc expects gfan to return type ideal. Probably this will change in near future.
         The return type will then be of type LIST_CMD