Changeset 398b15 in git for factory/cf_gcd.cc

Timestamp:

Feb 2, 1998, 9:58:49 AM (26 years ago)

Author:

Jens Schmidt <schmidt@…>

Branches:

(u'spielwiese', 'fe61d9c35bf7c61f2b6cbf1b56e25e2f08d536cc')

Children:

b0c783ccfcf6a8ce8a60e2e650e31f1b523d11cc

Parents:

f3b98ad1c11ea4bf6d3b9525f75480b2abf56cac

Message:

	* cf_gcd.cc (iextgcd, igcd): functions removed.  All references
	  replaced by `bextgcd()' and `bgcd()', resp.


git-svn-id: file:///usr/local/Singular/svn/trunk@1114 2c84dea3-7e68-4137-9b89-c4e89433aadc

File:

• factory/cf_gcd.cc (modified) (5 diffs)

factory/cf_gcd.cc

@@ -1 +1 @@
 /* emacs edit mode for this file is -*- C++ -*- */
-/* $Id: cf_gcd.cc,v 1.16 1998-01-27 10:18:33 pohl Exp $ */
+/* $Id: cf_gcd.cc,v 1.17 1998-02-02 08:58:43 schmidt Exp $ */
 
 #include <config.h>
@@ -115 +115 @@
 //}}}
 
-//{{{ CanonicalForm igcd ( const CanonicalForm & f, const CanonicalForm & g )
-//{{{ docu
-//
-// igcd() - return integer gcd of f and g.
-//
-// Calculates the integer gcd of f and g using the euclidean
-// algorithm if f and g are integers and we are not calculating
-// in Q.  Returns one in all other cases.  Normalizes result.
-//
-//}}}
-CanonicalForm
-igcd ( const CanonicalForm & f, const CanonicalForm & g )
-{
-    CanonicalForm a, b, c, dummy;
-
-    if ( f.inZ() && g.inZ() && ! isOn( SW_RATIONAL ) ) {
-        if ( f.sign() < 0 ) a = -f; else a = f;
-        if ( g.sign() < 0 ) b = -g; else b = g;
-        while ( ! b.isZero() ) {
-            divrem( a, b, dummy, c );
-            a = b;
-            b = c;
-        }
-        return a;
-    }
-    else
-        return 1;
-}
-//}}}
-
 //{{{ static CanonicalForm icontent ( const CanonicalForm & f, const CanonicalForm & c )
 //{{{ docu
@@ -179 +149 @@
 {
     return icontent( f, 0 );
-}
-//}}}
-
-//{{{ CanonicalForm iextgcd ( const CanonicalForm & f, const CanonicalForm & g, CanonicalForm & a, CanonicalForm & b )
-//{{{ docu
-//
-// iextgcd() - calculate extended integer gcd.
-//
-// Returns gcd(f, g) and a and b sucht that f*a+g*b=gcd(f, g).
-// The gcd is calculated using an extended euclidean polynomial
-// remainder sequence.  Normalizes result.
-//
-// Note: be sure you are calculating in Z, and not in Q!
-//
-//}}}
-CanonicalForm
-iextgcd ( const CanonicalForm & f, const CanonicalForm & g, CanonicalForm & a, CanonicalForm & b )
-{
-    CanonicalForm p0 = f, p1 = g;
-    CanonicalForm f0 = 1, f1 = 0, g0 = 0, g1 = 1, q, r;
-
-    while ( ! p1.isZero() ) {
-        divrem( p0, p1, q, r );
-        p0 = p1; p1 = r;
-        r = g0 - g1 * q;
-        g0 = g1; g1 = r;
-        r = f0 - f1 * q;
-        f0 = f1; f1 = r;
-    }
-    a = f0;
-    b = g0;
-    if ( p0.sign() < 0 ) {
-        p0 = -p0;
-        a = -a;
-        b = -b;
-    }
-    return p0;
 }
 //}}}
@@ -277 +210 @@
         f = F / cF;
         g = G / cG;
-        c = igcd( cF, cG );
+        c = bgcd( cF, cG );
     }
     cg = gcd( f.lc(), g.lc() );
@@ -550 +483 @@
     else  if ( f.inBaseDomain() )
         if ( g.inBaseDomain() )
-            return igcd( f, g );
+            return bgcd( f, g );
         else
             return cf_content( g, f );