Changeset d8db70 in git

Timestamp:

Oct 9, 2009, 11:05:18 AM (14 years ago)

Author:

Frank Seelisch <seelisch@…>

Branches:

(u'spielwiese', '828514cf6e480e4bafc26df99217bf2a1ed1ef45')

Children:

6094f40a4b25fd0a3a901bd854053d0df6b84df3

Parents:

b85e375dee0ef1d2f9b2272975f133610b000b0a

Message:

changes of extra system command 'changeRing' to ease generation of Maple, M2, and Magma scripts


git-svn-id: file:///usr/local/Singular/svn/trunk@12178 2c84dea3-7e68-4137-9b89-c4e89433aadc

File:

• Singular/extra.cc (modified) (3 diffs)

Singular/extra.cc

@@ -2 +2 @@
 *  Computer Algebra System SINGULAR      *
 *****************************************/
-/* $Id: extra.cc,v 1.323 2009-10-08 14:39:52 seelisch Exp $ */
+/* $Id: extra.cc,v 1.324 2009-10-09 09:05:18 seelisch Exp $ */
 /*
 * ABSTRACT: general interface to internals of Singular ("system" command)
@@ -2200 +2200 @@
           {
             /*
-            The following code creates a ring with characteristic fc, order dp and
-            varN variables with the following names: var(j) is j written to the
-            base of 26 with the digit '0' written as 'a', '1' as 'b', ..., and '25'
-            as 'z'.
-            I.e., var(1) has the name 'b', ..., var(25) the name 'z',
-                 var(26) the name 'ba', etc.
-            Afterwards, the new ring will become the current ring.
+            The following code creates and returns a ring with characteristic fc,
+            order dp and varN variables with the names "x1", "x2", ..., "x4711"
+            (in the case varN = 4711).
             The purpose of this rewriting is to eliminate indexed variables,
             as they may cause problems when generating scripts for Magma,
@@ -2214 +2210 @@
             newRing->ch = fc;
             newRing->N = varN;
+            char h[10];
             newRing->names = (char **) omAlloc0(varN * sizeof(char_ptr));
-            char* alphabet = "abcdefghijklmnopqrstuvwxyz";
-            char theName[10];
-            char tempChars[10];
-            int j; int k; int l;
             for (int i = 1; i <= varN; i++)
             {
-              k = i;
-              l = 9;
-              j = k % 26;
-              tempChars[l--] = alphabet[j];
-              k = (k - j) / 26;
-              while (k != 0)
-              {
-                j = k % 26;
-                tempChars[l--] = alphabet[j];
-                k = (k - j) / 26;
-              }
-              l++;
-              for (j = l; j < 10; j++) theName[j - l] = tempChars[j];
-              theName[10 - l] = '\0';
-              newRing->names[i - 1] = omStrDup(theName);
+              sprintf(h, "x%d", i);
+              newRing->names[i - 1] = omStrDup(h);
             }
             newRing->wvhdl = (int **)omAlloc0(2 * sizeof(int_ptr));