Changeset 89abd46 in git

Timestamp:

Jul 13, 2007, 4:05:14 PM (16 years ago)

Author:

Motsak Oleksandr <motsak@…>

Branches:

(u'spielwiese', '0d6b7fcd9813a1ca1ed4220cfa2b104b97a0a003')

Children:

5accf0ace0c30c09c866e4c16039ef64597f6a2c

Parents:

90ee8d1d1ab99050b0c30c21eadf342a5b681f01

Message:

*motsak: fix for the procedure SuperCommutative(). Note that there is a side effect!


git-svn-id: file:///usr/local/Singular/svn/trunk@10203 2c84dea3-7e68-4137-9b89-c4e89433aadc

File:

• Singular/LIB/nctools.lib (modified) (8 diffs)

Singular/LIB/nctools.lib

@@ -1 +1 @@
 ///////////////////////////////////////////////////////////////////////////////
-version="$Id: nctools.lib,v 1.26 2007-05-24 09:16:59 motsak Exp $";
+version="$Id: nctools.lib,v 1.27 2007-07-13 14:05:14 motsak Exp $";
 category="Noncommutative";
 info="
@@ -721 +721 @@
 "USAGE:   SuperCommutative([b,[e, [Q]]]);
 RETURN:  qring
-PURPOSE:  create the super-commutative algebra over a basering,
-NOTE:  activate this qring with the \"setring\" command
+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 to bo the basis G-algebra (without factor).
 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]
@@ -739 +740 @@
   int e = N;
 
-        def saveRing = basering;
+  def saveRing = basering;
   ideal Q = 0;
 
@@ -752 +753 @@
   }
 
-        if(size(#)>1)
-        {
-          if(typeof(#[2]) != "int")
-          {
-            ERROR("Last argument 'e' must be an integer!");
-            return();
-          }
-          e = #[2];
-        }
-
-        if(size(#)>2)
-        {
-          if(typeof(#[3]) != "ideal")
-          {
-            ERROR("Last argument 'Q' must be an ideal!");
-            return();
-          }
-          Q = #[3];
-        }
-        
+  if(size(#)>1)
+  {
+    if(typeof(#[2]) != "int")
+    {
+      ERROR("Last argument 'e' must be an integer!");
+      return();
+    }
+    e = #[2];
+  }
+
+  if(size(#)>2)
+  {
+    if(typeof(#[3]) != "ideal")
+    {
+      ERROR("Last argument 'Q' must be an ideal!");
+      return();
+    }
+    Q = #[3];
+  }
+
+/*
+  // Singular'(Hans) politics: no ring copyes! 
+  // in future ncalgebra() should return a new ring!!!
   list CurrRing = ringlist(basering);
   def @R = ring(CurrRing);
   setring @R; // @R;
+*/
 
   matrix @E = UpOneMatrix(N);
@@ -790 +795 @@
   ncalgebra(@E, 0);
 
-        ideal Q = fetch(saveRing, Q);
-        j = ncols(Q) + 1;
+  ideal Q = fetch(saveRing, Q);
+  j = ncols(Q) + 1;
 
   for ( i=e; i>=b; i--, j++ )
@@ -861 +866 @@
       if( c == -1 )
       {
-        if(i < b)
-        {
-                b = i;          
-        }
-        
-        if(j > e)
-        {
-                e = j;          
-        }
+        if(i < b)
+        {
+          b = i;        
+        }
+
+        if(j > e)
+        {
+          e = j;        
+        }
       } else
       { // should commute
@@ -915 +920 @@
 //  E;
 
-        ideal Q = fetch(saveRing, Q); // should belong to E!
-        Q = twostd(Q);
+  ideal Q = fetch(saveRing, Q); // should belong to E!
+  Q = twostd(Q);
 
 //  "Q = ", string(Q);
@@ -924 +929 @@
     if( NF(var(i)^2, Q) != 0 )
     {
-        setring saveRing;
+      setring saveRing;
       return("The current ring is not SCA! (Wrong quotient ideal)");
     }
   }
 
-        ////////////////////////////////////////////////////////////////////////
+  ////////////////////////////////////////////////////////////////////////
   // ok. it is a SCA!!!