Changeset bc7f20 in git for Singular/LIB/ncdecomp.lib

Timestamp:

Mar 25, 2005, 7:38:46 PM (19 years ago)

Author:

Viktor Levandovskyy <levandov@…>

Branches:

(u'spielwiese', '8e0ad00ce244dfd0756200662572aef8402f13d5')

Children:

fe40ad7908fc2170a79180bc025ccb5bceeab03f

Parents:

0c7cb809f77e6f72afc46162a675f1539bb715c1

Message:

*levandov: unified ideal-list handling for conveniency, minor corrections


git-svn-id: file:///usr/local/Singular/svn/trunk@7800 2c84dea3-7e68-4137-9b89-c4e89433aadc

File:

• Singular/LIB/ncdecomp.lib (modified) (6 diffs)

Singular/LIB/ncdecomp.lib

@@ -1 +1 @@
 ///////////////////////////////////////////////////////////////////////////////
-version="$Id: ncdecomp.lib,v 1.6 2005-02-23 18:10:46 levandov Exp $";
+version="$Id: ncdecomp.lib,v 1.7 2005-03-25 18:38:46 levandov Exp $";
 category="Noncommutative";
 info="
@@ -17 +17 @@
 CenCharDec(I,C);        central character decomposition of I w.r.t. C
 IntersectWithSub(M,Z);  intersection of M with the subalgebra, generated
-by pairwise commutative elements.
+by pairwise commutative elements of Z.
 ";
 
@@ -176 +176 @@
 }
 ///////////////////////////////////////////////////////////////////////////////
-proc CenCharDec(module I, list Center)
-"USAGE:  CenCharDec(I, C);  I a module, C a list of generators of the center;
+proc CenCharDec(module I, def #)
+"USAGE:  CenCharDec(I, C);  I a module, C an ideal/list of generators of the center;
+PURPOSE: compute a finite central character decomposition (or point out that there is no finite one),
 RETURN:  a list L, where each entry consists of three records:
-@*           L[*][1] is the central character in terms of central elements, 
-@*           L[*][2] is the Groebner basis of the corresponding weight module, 
-@*           L[*][3] is the K-dimension of the weight module;
+@*       L[*][1] ('ideal' type), the central character as the maximal ideal in the center, 
+@*       L[*][2] ('module' type), the Groebner basis of the weight module, corresponding to the character, 
+@*       L[*][3] ('int' type) is the K-dimension of the weight module (-1 is returned for an infinite dimension);
 NOTE:     some modules have no finite decomposition (in such case one
           gets warning message)
@@ -188 +189 @@
 "
 {
+  list Center;
+  if (typeof(#) == "ideal")
+  {
+    int cc;
+    ideal tmp = ideal(#);
+    for (cc=1; cc<=size(tmp); cc++)
+    {
+      Center[cc] = tmp[cc];
+    }
+    kill tmp;
+  }
+  if (typeof(#) == "list")
+  {
+    Center = #;
+  }
 // M = A/I
 //1. Find the Zariski closure of Supp_Z M
@@ -308 +324 @@
 }
 ///////////////////////////////////////////////////////////////////////////////
-proc IntersectWithSub (ideal M, ideal Z)
-"USAGE:  IntersectWithSub(M,Z),  M an ideal, Z an ideal of pairwise commutative elements
+proc IntersectWithSub (ideal M, def #)
+"USAGE:  IntersectWithSub(M,Z),  M an ideal, Z an ideal/list of pairwise commutative elements
 PURPOSE: computes an intersection of M with the subalgebra, generated by Z
 RETURN:  ideal (of two--sided generators, not a Groebner basis!)
@@ -316 +332 @@
 "
 {
+  ideal Z;
+  if (typeof(#) == "list")
+  {
+    int cc;
+    list tmp = #;
+    for (cc=1; cc<=size(tmp); cc++)
+    {
+      Z[cc] = tmp[cc];
+    }
+    kill tmp;
+  }
+  if (typeof(#) == "ideal")
+  {
+    Z = #;
+  }
   // returns a submodule of M, equal to M \cap Z
   // correctness: Z should consists of pairwise