Changeset 7e0aa3 in git

Timestamp:

Dec 9, 2005, 10:12:53 AM (18 years ago)

Author:

Wilfred Pohl <pohl@…>

Branches:

(u'spielwiese', '4a9821a93ffdc22a6696668bd4f6b8c9de3e6c5f')

Children:

f0d1e8ff9bbee3ecdc215a126853bef13df180db

Parents:

5282ba08768ae8313d001b2e19108ef82902d2a9

Message:

power


git-svn-id: file:///usr/local/Singular/svn/trunk@8838 2c84dea3-7e68-4137-9b89-c4e89433aadc

File:

• factory/canonicalform.cc (modified) (2 diffs)

factory/canonicalform.cc

@@ -1 +1 @@
 /* emacs edit mode for this file is -*- C++ -*- */
-/* $Id: canonicalform.cc,v 1.36 2005-12-09 08:35:37 Singular Exp $ */
+/* $Id: canonicalform.cc,v 1.37 2005-12-09 09:12:53 pohl Exp $ */
 
 #include <config.h>
@@ -1693 +1693 @@
 {
     ASSERT( n >= 0, "illegal exponent" );
-    if ( f == 0 )
-        return 0;
-    else  if ( f == 1 )
+    if ( f.isZero() || f.isOne() )
         return f;
-    else  if ( f == -1 ) {
+    else  if ( (-f).isOne() ) {
         if ( n % 2 == 0 )
-            return 1;
+            return -f;
         else
-            return -1;
+            return f;
     }
     else  if ( n == 0 )
-        return 1;
+        return f.genOne();
     //else if (f.inGF())
     //{
     //}
     else {
-        CanonicalForm result = f;
-        for ( int i = 1; i < n; i++ )
-            result *= f;
-        return result;
+        CanonicalForm g,h;
+        h=f;
+        while(n%2==0)
+        {
+          h*=h;
+          n/=2;
+        }
+        g=h;
+        while(1)
+        {
+          n/=2;
+          if(n==0)
+            return g;
+          h*=h;
+          if(n%2!=0) g*=h;
+        }
     }
 }