Changeset 2cdfc8 in git for Singular/LIB/paraplanecurves.lib

Timestamp:

Mar 22, 2011, 10:33:58 AM (13 years ago)

Author:

Frank Seelisch <seelisch@…>

Branches:

(u'spielwiese', '4a9821a93ffdc22a6696668bd4f6b8c9de3e6c5f')

Children:

21ee926ee8ae7b87879f1075406bc488cb810470

Parents:

a41cdb0b52788c0c83732f7ac9d14650d4908bfd

Message:

changed optional param of paraplanecurve to string, extended doc for return value (Burcin's suggestions)

git-svn-id: file:///usr/local/Singular/svn/trunk@14029 2c84dea3-7e68-4137-9b89-c4e89433aadc

File:

• Singular/LIB/paraplanecurves.lib (modified) (3 diffs)

Singular/LIB/paraplanecurves.lib

@@ -228 +228 @@
 ///////////////////////////////////////////////////////////////////////////////
 proc paraPlaneCurve(poly f, list #)
-"USAGE:  paraPlaneCurve(f [, c]); f poly , c optional integer@*
-         optional integer c can be: @*
-         1: compute integral basis via normalization. @*
-         2: make local analysis of singularities first and apply normalization
-            separately. @*
+"USAGE:  paraPlaneCurve(f [, s]); f poly , s optional string@*
+         optional string s can be: @*
+         'normal': compute integral basis via normalization. @*
+         'local':  make local analysis of singularities first and apply
+                   normalization separately. @*
          The default is 2. @*
 ASSUME:  The basering must be a polynomial ring in three variables, say x,y,z,
@@ -240 +240 @@
          (see @ref{genus}). @*
          These conditions will be checked automatically.
-RETURN:  ring with an ideal PARA.
+RETURN:  ring with an ideal PARA which contains a rational parametrization of
+         the rational plane curve given by f; the ground field of the returned
+         polynomial ring is either Q or some algebraic extension Q(a); PARA
+         consists of three generators that parametrize the three coordinates
+         of the rational curve
 THEORY:  After a first step, realized by a projective automorphism in the
          procedure adjointIdeal, C satisfies: @*
@@ -272 +276 @@
 "
 {
-  if(size(#)==0) {int choice = 2;} else {int choice = #[1];}
+  int choice = 2;
+  if (size(#) != 0)
+  {
+    if (typeof(#[1]) == "string")
+    {
+      string s = string(#[1]);
+      if (s == "normal") { choice = 1; }
+      else
+      {
+        if (s == "local") { choice = 2; }
+        else { ERROR("expected optional argument to be either"
+                   + " 'local' or 'normal'"); }
+      }
+    }
+    else { ERROR("expected optional argument to be a string"); }
+  }
   def Roriginal = basering;
   /*checking assumptions and handling the conic case*/