Changeset 0ffc823 in git for kernel/ratgring.cc

Timestamp:

Feb 27, 2009, 8:30:47 PM (15 years ago)

Author:

Viktor Levandovskyy <levandov@…>

Branches:

(u'spielwiese', 'd0474371d8c5d8068ab70bfb42719c97936b18a6')

Children:

8066e80d7cea5de772f7b10b2b1930521cb72523

Parents:

f58aa61ada5934435d94d1d486fb70912543c11a

Message:

*levandov: early unit detection in rational GB


git-svn-id: file:///usr/local/Singular/svn/trunk@11495 2c84dea3-7e68-4137-9b89-c4e89433aadc

File:

• kernel/ratgring.cc (modified) (4 diffs)

kernel/ratgring.cc

@@ -7 +7 @@
  *  Author:  levandov (Viktor Levandovsky)
  *  Created: 8/00 - 11/00
- *  Version: $Id: ratgring.cc,v 1.22 2009-02-26 14:24:23 Singular Exp $
+ *  Version: $Id: ratgring.cc,v 1.23 2009-02-27 19:30:47 levandov Exp $
  *******************************************************************/
 #include "mod2.h"
@@ -416 +416 @@
   }
 
+  if ( (p_LmIsConstantRat(p1,r)) || (p_LmIsConstantRat(p2,r)) )
+  {
+    p_Delete(&p1,r);
+    p_Delete(&p2,r);
+    return( NULL );
+  }
+
+
 /* note: prod. crit does not apply! */
   poly pL=pOne();
@@ -528 +536 @@
     return(NULL);
   }
+
+  if (p_LmIsConstantRat(p1,r))
+  {
+    return( NULL );
+  }
+
 
   int is = ishift; /* TODO */
@@ -794 +808 @@
   omFree(L);
 }
-#endif
+
+// test if monomial is a constant, i.e. if all exponents and the component
+// is zero
+BOOLEAN p_LmIsConstantRat(const poly p, const ring r)
+{
+  if (p_LmIsConstantCompRat(p, r))
+    return (p_GetComp(p, r) == 0);
+  return FALSE;
+}
+
+// test if the monomial is a constant as a vector component
+// i.e., test if all exponents are zero
+BOOLEAN p_LmIsConstantCompRat(const poly p, const ring r)
+{
+  int i = r->real_var_end;
+
+  while ( (p_GetExp(p,i,r)==0) && (i>=r->real_var_start))
+  {
+    i--;
+  }
+  return ( i+1 == r->real_var_start );
+}
+
+#endif