Changeset 1b5f4b in git

Timestamp:

Oct 30, 2007, 10:04:42 PM (16 years ago)

Author:

Motsak Oleksandr <motsak@…>

Branches:

(u'spielwiese', '4a9821a93ffdc22a6696668bd4f6b8c9de3e6c5f')

Children:

054f36c953adc6d7ede471fd6c7417fd55233fc3

Parents:

b9ed9219019a539488427520e4fd4f0a1f50e0a0

Message:

*motsak: fixes to SuperCommutative due to Simon King


git-svn-id: file:///usr/local/Singular/svn/trunk@10358 2c84dea3-7e68-4137-9b89-c4e89433aadc

File:

• Singular/LIB/nctools.lib (modified) (14 diffs)

Singular/LIB/nctools.lib

@@ -1 +1 @@
 ///////////////////////////////////////////////////////////////////////////////
-version="$Id: nctools.lib,v 1.33 2007-10-30 17:27:44 motsak Exp $";
+version="$Id: nctools.lib,v 1.34 2007-10-30 21:04:42 motsak Exp $";
 category="Noncommutative";
 info="
@@ -717 +717 @@
 ///////////////////////////////////////////////////////////////////////////////
 proc SuperCommutative(list #)
-"USAGE:   SuperCommutative([b,[e, [Q]]]);
+"USAGE:   SuperCommutative([b,[e, [Q, [flag]]]]);
 RETURN:  qring
 PURPOSE:  create the super-commutative algebra (as a GR-algebra) 'over' a basering,
 NOTE: activate this qring with the \"setring\" command. 
-NOTE: as a side effect the basering will be changed (if not in a commutative case) to bo the ground G-algebra (without factor).
-NOTE: if b==e then the resulting ring is commutative.
+NOTE: if b==e then the resulting ring is commutative unles 'flag' is given and non-zero.
 THEORY: given a basering, this procedure introduces the anticommutative relations x(j)x(i)=-x(i)x(j) for all e>=j>i>=b,
 @* moreover, creates a factor algebra modulo the two-sided ideal, generated by x(b)^2, ..., x(e)^2[ + Q]
@@ -728 +727 @@
 "
 {
+
+// NOTE: as a side effect the basering will be changed (if not in a commutative case) to bo the ground G-algebra (without factor).
   int fprot = (find(option(),"prot") != 0);
   
@@ -743 +744 @@
   int b = 1;
   int e = N;
-
+  int flag = 0;
+  
   ideal Q = 0;
 
@@ -750 +752 @@
     if(typeof(#[1]) != "int")
     {
-      ERROR("First argument 'b' must be an integer!");
+      ERROR("The argument 'b' must be an integer!");
       return();
     }    
@@ -757 +759 @@
     if((b < 1)||(b > N))
     {
-      ERROR("First argument 'b' must within [1..nvars(basering)]!");
+      ERROR("The argument 'b' must within [1..nvars(basering)]!");
       return();
     }    
@@ -767 +769 @@
     if(typeof(#[2]) != "int")
     {
-      ERROR("Second argument 'e' must be an integer!");
+      ERROR("The argument 'e' must be an integer!");
       return();
     }
@@ -774 +776 @@
     if((e < 1)||(e > N))
     {
-      ERROR("Second argument 'e' must within [1..nvars(basering)]!");
+      ERROR("The argument 'e' must within [1..nvars(basering)]!");
       return();
     }
@@ -780 +782 @@
     if(e < b)
     {
-      ERROR("Second argument 'e' must be bigger or equal to 'b'!");
+      ERROR("The argument 'e' must be bigger or equal to 'b'!");
       return();
     }
-
   }
 
@@ -790 +791 @@
     if(typeof(#[3]) != "ideal")
     {
-      ERROR("Last argument 'Q' must be an ideal!");
+      ERROR("The argument 'Q' must be an ideal!");
       return();
     }
     Q = #[3];
   }
-
-  if( b == e ) // commutative ring!!!
+  
+  if(size(#)>3)
+  {
+    if(typeof(#[4]) != "int")
+    {
+      ERROR("The argument 'flag' must be an integer!");
+      return();
+    }
+    flag = #[4];
+  }
+
+  int iSavedDegBoung = degBound; 
+
+  if( (b == e) && (flag == 0) ) // commutative ring!!!
   {
     if( fprot == 1)
@@ -802 +815 @@
       print("Warning: (b==e) means that the resulting ring will be commutative!");
     }
+    
+    degBound=0;
     Q = std(Q + (var(b)^2));
+    degBound = iSavedDegBoung;
+    
     qring @EA = Q; // and it will be internally commutative as well!!!
+        
     return(@EA);    
   }
@@ -815 +833 @@
 */
 
-  if (char(basering)==2) // commutative ring!!!
+  if( (char(basering)==2) && (flag == 0) )// commutative ring!!!
   {
     if( fprot == 1)
@@ -829 +847 @@
     }
     
+    degBound=0;    
     Q = std(Q);
+    degBound = iSavedDegBoung;
+    
     qring @EA = Q; // and it will be internally commutative as well!!!
     return(@EA);      
@@ -870 +891 @@
     print("Q:", @Q);
   }
-  
+
+  degBound=0;    
   @Q = twostd(@Q); // must be computed within the ground G-algebra => problems with local orderings!
+  degBound = iSavedDegBoung;
   
   qring @EA = @Q;