Changeset d4f44f in git

Timestamp:

Jul 15, 2009, 4:43:52 PM (14 years ago)

Author:

Motsak Oleksandr <motsak@…>

Branches:

(u'jengelh-datetime', 'ceac47cbc86fe4a15902392bdbb9bd2ae0ea02c6')(u'spielwiese', '0604212ebb110535022efecad887940825b97c3f')

Children:

0179d569cebe4081f964479a71818cd5d80626ee

Parents:

94aed9b17cc0b8aea93a2773b33dbebeeffffb02

Message:

the procedure sort is back to the original, description improvement & new example


git-svn-id: file:///usr/local/Singular/svn/trunk@11980 2c84dea3-7e68-4137-9b89-c4e89433aadc

File:

• Singular/LIB/general.lib (modified) (4 diffs)

Singular/LIB/general.lib

@@ -3 +3 @@
 //eric, added absValue 11.04.2002
 ///////////////////////////////////////////////////////////////////////////////
-version="$Id: general.lib,v 1.63 2009-07-10 18:52:05 motsak Exp $";
+version="$Id: general.lib,v 1.64 2009-07-15 14:43:52 motsak Exp $";
 category="General purpose";
 info="
@@ -744 +744 @@
          entries of v must be pairwise distinct to get a permutation id.
          Zero generators of ideal/module are deleted
+         If 'o' is given, the input is sorted by considering leading terms
+         w.r.t. the new ring ordering given by 'o'
 EXAMPLE: example sort; shows an example
 "
@@ -765 +767 @@
       if ( typeof(#[1])=="string" )
       {
-         if( typeof(id)=="matrix" )
-         {
-           module ID = lead(module(id));
-         } else
-         {
-           def ID = lead(id);
-         }
          execute("ring r1 =("+charstr(P)+"),("+varstr(P)+"),("+#[1]+");");
-         def i = imap(P,ID);
+         def i = imap(P,id);
          v = sortvec(i);
          setring P;
@@ -848 +843 @@
 
    sort(v,"Dp",1)[1];   // sort v w.r.t (total sum, reverse lex)
+
+   // Note that in general: lead(sort(M)) != sort(lead(M)), e.g:
+   module M = [0, 1, 1, 0], [1, 0, 0, 1]; M;
+   sort(lead(M), "c, dp")[1]; 
+   lead(sort(M, "c, dp")[1]);  
+
+   // In order to sort M wrt a NEW ordering by considering OLD leading
+   // terms use one of the following equivalent commands:
+   module( M[ sort(lead(M), "c,dp")[2] ] ); 
+   sort( M, sort(lead(M), "c,dp")[2] )[1]; 
 }
 ///////////////////////////////////////////////////////////////////////////////