Changeset 936ad6 in git

Timestamp:

Jun 24, 2005, 3:40:06 PM (18 years ago)

Author:

Nadine Cremer <cremer@…>

Branches:

(u'spielwiese', '91fdef05f09f54b8d58d92a472e9c4a43aa4656f')

Children:

3781a22b49bf6807b4bfa152e670e186f67e6e1a

Parents:

c3b1728b9644f0affd1ff817d9ed16fc1294f32e

Message:

*cremer: F's are fine, start with G's :-)


git-svn-id: file:///usr/local/Singular/svn/trunk@8403 2c84dea3-7e68-4137-9b89-c4e89433aadc

File:

• Singular/LIB/lejeune.lib (modified) (10 diffs)

Singular/LIB/lejeune.lib

@@ -1 +1 @@
 
 //-*- mode:C++;-*-
-// $Id: lejeune.lib,v 1.10 2005-06-24 12:01:09 cremer Exp $
+// $Id: lejeune.lib,v 1.11 2005-06-24 13:40:06 cremer Exp $
 
 
@@ -18 +18 @@
                          N is number of variables of input f
     formaldiff(f,k);     computes the formal derivatives D_I with |I|<k
-    f_setstep(f,H);      iterates the steps given by H, saved in f_set             f_set(f,H);          returns the set F corresponding to H as described by
+    f_setstep(f,H);      iterates the steps given by H, saved in f_set            
+    f_set(f,H);          returns the set F corresponding to H as described by
                          M. Lejeune
   ";
 
 
-LIB "ring.lib";                       // need procedures from these libs
+LIB "ring.lib";
 LIB "general.lib";
-
-
+LIB "primdec.lib";
+LIB "standard.lib";
+
+////////////////////////////////////////////////////////////////////////////
+//                 COMPUTATION OF THE F's
+////////////////////////////////////////////////////////////////////////////
 
 proc f_set (poly f,intvec H)         // puts together the single steps from
@@ -35 +40 @@
   def R=ringchange(b-1);
   setring R;
-  list l;
+  ideal J,I;
   for(i=2;i<=b;i++)
    {
@@ -41 +46 @@
      def tmp=f_setstep(f,intvec(H[1..i]));
      setring R;
-     ideal I=imap(tmp,resultf_set);
-     l[i-1]=I;
+     I=imap(tmp, resultf_set);
+     kill tmp;
+     J=J,I;
+     
    }
-  l;
+  J=simplify(J,2);
+  J=slimgb(radical(J));
+  J;
   return(R);
 }
+
 
 
@@ -52 +62 @@
 { 
   int p;                              // loop variable
-  int m_0=ord(f);
+  int m_0=order(f); 
+  int startvar=nvars(basering);                        
   int b=size(H);
   int c=sum(H,1..b-1);
@@ -76 +87 @@
 
 
-
-
+////////////////////////////////////////////////////////////////////////////
+//              PREPARATORY WORK: plugging in and differentiating
+////////////////////////////////////////////////////////////////////////////
 
 proc formaldiff (poly f,int i,int a,int k)
@@ -111 +123 @@
   export(resultdiff);                // exports the result
   return(R);                         // return the ring
-  
-}
-
+}
+
+
+////////////////////////////////////////////////////////////////////////////
 
 
@@ -131 +144 @@
   return(R);                        // return ring (ring change!)
 }
-
-
-
-proc ringchange (int i)
-{
-  int startvar;
-  startvar=nvars(basering);
-  export(startvar);       
-  def R=changevar(""+varstr(basering)+",t,"+variables(startvar,i)+"");// change
-  return(R);                 // return the ring, needed in future proc
-}
-
-
-
-proc variables (int k,int i)
-{
-  list l;
-  int s,u;                              // loop variables
-  string str;               
-  for (u=1;u<=k;u++) 
-   {
-     for (s=1;s<=i;s++)
-     {
-       str=""+a_z(u)+"("+string(s)+")"; // creates new variables    
-       l[(u-1)*i+s]=str;                // saves them in a list
-     }
-   } 
-  string str1=string(l);                // makes the list into a string,
-  return(str1);                         // (needed for ring change)
-}
-
-
-proc a_z (int n)                        // returns nth letter of the alphabet
-{ 
-  if(1>n>26)                     // input admissible?
-   { 
-     "n must range between 1 and 26!";
-      return(0); 
-   } 
-  string s="ring r=0,("+A_Z("a",n)+"),ds;"; 
-  execute(s); 
-  return (string(var(n))); 
-} 
 
 
@@ -196 +166 @@
 } 
 
-
+////////////////////////////////////////////////////////////////////////////
+//                     CONSTRUCTING the new ring(s)
+////////////////////////////////////////////////////////////////////////////
+
+proc ringchange (int i)
+{    
+  def R=changevar(""+varstr(basering)+",t,"+variables(startvar,i)+"");// change
+  return(R);                 // return the ring, needed in future proc
+}
+
+
+
+proc variables (int k,int i)
+{
+  list l;
+  int s,u;                              // loop variables
+  string str;               
+  for (u=1;u<=k;u++) 
+   {
+     for (s=1;s<=i;s++)
+     {
+       str=""+a_z(u)+"("+string(s)+")"; // creates new variables    
+       l[(u-1)*i+s]=str;                // saves them in a list
+     }
+   } 
+  string str1=string(l);                // makes the list into a string,
+  return(str1);                         // (needed for ring change)
+}
+
+
+proc a_z (int n)                        // returns nth letter of the alphabet
+{ 
+  if(1>n>26)                     // input admissible?
+   { 
+     "n must range between 1 and 26!";
+      return(0); 
+   } 
+  string s="ring r=0,("+A_Z("a",n)+"),ds;"; 
+  execute(s); 
+  return (string(var(n))); 
+} 
+
+
+////////////////////////////////////////////////////////////////////////////
+//                        AUXILIARY procedures     
+////////////////////////////////////////////////////////////////////////////
 
 
@@ -209 +224 @@
 return(I);
 }
+
+
+
+proc order (poly f)
+{
+  poly g=homog(f,var(1));
+  int k=deg(g);
+  int i;
+  for(i=1;i<k;i++)
+    {
+      if(jet(f,i)!=0)
+        {
+          return(i);
+        }
+    }
+}