Changeset 331fd0 in git for libpolys/polys/ext_fields/algext.cc

Timestamp:

Sep 27, 2011, 2:50:46 PM (12 years ago)

Author:

Hans Schoenemann <hannes@…>

Branches:

(u'spielwiese', '8e0ad00ce244dfd0756200662572aef8402f13d5')

Children:

6f6b9df159c9c68abfcfe9d2008f357892b7191a

Parents:

7f10dcde67f050fefbfeef12ce8d0108889fb6cc

git-author:

Hans Schoenemann <hannes@mathematik.uni-kl.de>2011-09-27 14:50:46+02:00

git-committer:

Mohamed Barakat <mohamed.barakat@rwth-aachen.de>2011-11-09 16:13:37+01:00

Message:

fix: naSetMap

File:

• libpolys/polys/ext_fields/algext.cc (modified) (5 diffs)

libpolys/polys/ext_fields/algext.cc

@@ -45 +45 @@
 
 #include "ext_fields/algext.h"
+#define TRANSEXT_PRIVATES 1
+#include "ext_fields/transext.h"
 
 #ifdef LDEBUG
@@ -562 +564 @@
 }
 
+number naCopyExt(number a, const coeffs src, const coeffs dst)
+{
+  fraction fa=(fraction)a;
+  return (number)p_Copy(NUM(fa),src->extRing);
+}
+
 /* assumes that src = Q, dst = Z/p(a) */
 number naMap0P(number a, const coeffs src, const coeffs dst)
@@ -603 +611 @@
   int h = 0; /* the height of the extension tower given by dst */
   coeffs bDst = nCoeff_bottom(dst, h); /* the bottom field in the tower dst */
+  coeffs bSrc = nCoeff_bottom(src, h); /* the bottom field in the tower src */
   
   /* for the time being, we only provide maps if h = 1 and if b is Q or
      some field Z/pZ: */
+  if (h==0)
+  {
+    if (nCoeff_is_Q(src) && nCoeff_is_Q(bDst))
+      return naMap00;                            /// Q     -->  Q(a)
+    if (nCoeff_is_Zp(src) && nCoeff_is_Q(bDst))
+      return naMapP0;                            /// Z/p   -->  Q(a)
+    if (nCoeff_is_Q(src) && nCoeff_is_Zp(bDst))
+      return naMap0P;                            /// Q      --> Z/p(a)
+    if (nCoeff_is_Zp(src) && nCoeff_is_Zp(bDst))
+    {
+      if (src->ch == dst->ch) return naMapPP;    /// Z/p    --> Z/p(a)
+      else return naMapUP;                       /// Z/u    --> Z/p(a)
+    }
+  }
   if (h != 1) return NULL;
   if ((!nCoeff_is_Zp(bDst)) && (!nCoeff_is_Q(bDst))) return NULL;
-  
-  if (nCoeff_is_Q(src) && nCoeff_is_Q(bDst))
-    return naMap00;                                      /// Q     -->  Q(a)
-  
-  if (nCoeff_is_Zp(src) && nCoeff_is_Q(bDst))
-    return naMapP0;                                      /// Z/p   -->  Q(a)
-  
-  if (nCoeff_is_Q(src) && nCoeff_is_Zp(bDst))
-    return naMap0P;                                      /// Q      --> Z/p(a)
-  
-  if (nCoeff_is_Zp(src) && nCoeff_is_Zp(bDst))
-  {
-    if (src->ch == dst->ch) return naMapPP;              /// Z/p    --> Z/p(a)
-    else return naMapUP;                                 /// Z/u    --> Z/p(a)
-  }
-  
-  coeffs bSrc = nCoeff_bottom(src, h); /* the bottom field in the tower src */
-  if (h != 1) return NULL;
   if ((!nCoeff_is_Zp(bSrc)) && (!nCoeff_is_Q(bSrc))) return NULL;
   
@@ -632 +637 @@
     if (strcmp(rRingVar(0, src->extRing),
                rRingVar(0, dst->extRing)) == 0)
-      return naCopyMap;                                  /// Q(a)   --> Q(a)
+    {
+      if (src->type==n_algExt)
+         return naCopyMap;                       /// Q(a)   --> Q(a)
+      else
+         return naCopyExt;
+    }
     else
-      return NULL;                                       /// Q(b)   --> Q(a)
+      return NULL;                               /// Q(b)   --> Q(a)
   }
   
@@ -641 +651 @@
     if (strcmp(rParameter(src->extRing)[0],
                rParameter(dst->extRing)[0]) == 0)
-      return naCopyMap;                                  /// Z/p(a) --> Z/p(a)
+    {
+      if (src->type==n_algExt)
+        return naCopyMap;                        /// Z/p(a) --> Z/p(a)
+      else
+         return naCopyExt;
+    }
     else
-      return NULL;                                       /// Z/p(b) --> Z/p(a)
+      return NULL;                               /// Z/p(b) --> Z/p(a)
   }