Changeset f7951d in git

Timestamp:

Mar 10, 2021, 3:49:00 PM (3 years ago)

Author:

Hans Schoenemann <hannes@…>

Branches:

(u'spielwiese', 'fe61d9c35bf7c61f2b6cbf1b56e25e2f08d536cc')

Children:

24457e03b41762fa464203e9f37e01f02fce24683648b2bef793a083d375af65419598beca5015cd77054fb78f4461a6ea2947231805a4b0df8a2bf2e116149bc2442a2ba73ebb392585573a36abcafd

Parents:

2fef40de8fd04416484636ccf6b77fe2038041f4

Message:

add fglmUni, fgmlQuot

Location:

Singular

Files:

• fglm.cc (modified) (4 diffs)
• fglm.h (modified) (2 diffs)

Singular/fglm.cc

@@ -348 +348 @@
 }
 
+ideal fglmQuot( ideal first, poly second )
+{
+    FglmState state = FglmOk;
+
+    ideal sourceIdeal = first;
+    poly quot = second;
+    ideal destIdeal = NULL;
+
+    state = fglmIdealcheck( sourceIdeal );
+    if ( state == FglmOk )
+    {
+      if ( quot == NULL ) state= FglmPolyIsZero;
+      else if ( pIsConstant( quot ) ) state= FglmPolyIsOne;
+    }
+
+    if ( state == FglmOk )
+    {
+      if ( fglmquot( sourceIdeal, quot, destIdeal ) == FALSE )
+        state= FglmNotReduced;
+    }
+
+    switch (state)
+    {
+        case FglmOk:
+            break;
+        case FglmHasOne:
+            destIdeal= idInit(1,1);
+            (destIdeal->m)[0]= pOne();
+            state= FglmOk;
+            break;
+        case FglmNotZeroDim:
+            WerrorS( "The ideal has to be 0-dimensional" );
+            destIdeal= idInit(1,1);
+            break;
+        case FglmNotReduced:
+            WerrorS( "The poly has to be reduced" );
+            destIdeal= idInit(1,1);
+            break;
+        case FglmPolyIsOne:
+            int k;
+            destIdeal= idInit( IDELEMS(sourceIdeal), 1 );
+            for ( k= IDELEMS( sourceIdeal )-1; k >=0; k-- )
+              (destIdeal->m)[k]= pCopy( (sourceIdeal->m)[k] );
+            state= FglmOk;
+            break;
+        case FglmPolyIsZero:
+            destIdeal= idInit(1,1);
+            (destIdeal->m)[0]= pOne();
+            state= FglmOk;
+            break;
+        default:
+            destIdeal= idInit(1,1);
+    }
+
+    return destIdeal;
+}
+
 // fglmQuotProc: Calculate I:f with FGLM methods.
 // Checks the input-data, and calls fglmquot (see fglmzero.cc).
@@ -415 +472 @@
 } // fglmQuotProt
 
-// The main function for finduni().
-// Checks the input-data, and calls FindUnivariateWrapper (see fglmzero.cc).
-// Returns an ideal containing the univariate Polynomials or 0 if an error
-// has occoured.
-BOOLEAN
-findUniProc( leftv result, leftv first )
+ideal findUni( ideal first )
 {
     ideal sourceIdeal;
@@ -426 +478 @@
     FglmState state;
 
-    sourceIdeal = (ideal)first->Data();
-
-    assumeStdFlag( first );
+    sourceIdeal = first;
+
     state= fglmIdealcheck( sourceIdeal );
     if ( state == FglmOk )
@@ -470 +521 @@
             break;
         case FglmNotZeroDim:
+            WerrorS( "The ideal has to be 0-dimensional" );
+            destIdeal= idInit(1,1);
+            break;
+        case FglmNotReduced:
+            Werror( "The ideal has to be reduced" );
+            destIdeal= idInit(1,1);
+            break;
+        default:
+            destIdeal= idInit(1,1);
+    }
+
+    return destIdeal;
+}
+// The main function for finduni().
+// Checks the input-data, and calls FindUnivariateWrapper (see fglmzero.cc).
+// Returns an ideal containing the univariate Polynomials or 0 if an error
+// has occoured.
+BOOLEAN
+findUniProc( leftv result, leftv first )
+{
+    ideal sourceIdeal;
+    ideal destIdeal = NULL;
+    FglmState state;
+
+    sourceIdeal = (ideal)first->Data();
+
+    assumeStdFlag( first );
+    state= fglmIdealcheck( sourceIdeal );
+    if ( state == FglmOk )
+    {
+      // check for special cases: if the input contains
+      // univariate polys, try to reduce the problem
+      int i,k;
+      int count=0;
+      BOOLEAN * purePowers = (BOOLEAN *)omAlloc0( currRing->N*sizeof( BOOLEAN ) );
+      for ( k= IDELEMS( sourceIdeal ) - 1; k >= 0; k-- )
+      {
+        if((i=pIsUnivariate(sourceIdeal->m[k]))>0)
+        {
+          if (purePowers[i-1]==0)
+          {
+            purePowers[i-1]=k;
+            count++;
+            if (count==currRing->N) break;
+          }
+        }
+      }
+      if (count==currRing->N)
+      {
+        destIdeal=idInit(currRing->N,1);
+        for(k=currRing->N-1; k>=0; k--) destIdeal->m[k]=pCopy(sourceIdeal->m[purePowers[k]]);
+      }
+      omFreeSize((ADDRESS)purePowers, currRing->N*sizeof( BOOLEAN ) );
+      if (destIdeal!=NULL)
+            state = FglmOk;
+      else if ( FindUnivariateWrapper( sourceIdeal, destIdeal ) == FALSE )
+            state = FglmNotReduced;
+    }
+    switch (state)
+    {
+        case FglmOk:
+            break;
+        case FglmHasOne:
+            destIdeal= idInit(1,1);
+            (destIdeal->m)[0]= pOne();
+            state= FglmOk;
+            break;
+        case FglmNotZeroDim:
             Werror( "The ideal %s has to be 0-dimensional", first->Name() );
             destIdeal= NULL;

Singular/fglm.h

@@ -24 +24 @@
 //  Returns TRUE if an error occoured.
 BOOLEAN fglmQuotProc( leftv result, leftv first, leftv second );
+ideal fglmQuot( ideal first, poly second );
 
 // FindUnivariatePolys (test)
@@ -30 +31 @@
 // wrapper for FindUnivariatePolys (test)
 BOOLEAN findUniProc( leftv result, leftv first);
+ideal findUni( ideal first );
 
 // homogeneous FGLM