Re: complex bug

>
>  When I try to make a complex with the procedure <make-polar> in 
> scheme48 1.8, the interpreter always returns an error,
> said that "wrong-type-argument".
>
> So I checked r5rs fund that I did nothing wrong.
>
> I use scheme48 in winXP.
> with a picture of the problem.

Scheme48 doesn't have make-polar as yet. The following patch works for 
me (for version 1.8).

diff -r 1f349e4f8f3b scheme/rts/xnum.scm
--- a/scheme/rts/xnum.scm    Wed Mar 05 09:16:57 2008 +0100
+++ b/scheme/rts/xnum.scm    Wed Jul 30 04:37:46 2008 +0400
@@ -133,6 +133,7 @@
 (define-opcode-extension denominator    &denominator)
 
 (define-opcode-extension make-rectangular &make-rectangular)
+(define-opcode-extension make-polar &make-polar)
 
 (define-opcode-extension exp   &exp)
 (define-opcode-extension log   &log)
@@ -358,3 +359,8 @@
     (if (char=? c (string-ref s i))
         i
         (loop (+ i 1))))))
+
+; make-polar
+(define-method &make-polar ((m :real) (theta :real))
+           (make-rectangular (* m (cos theta))
+                   (* m (sin theta))))


The code was borrowed from http://paste.lisp.org/display/30061. I hope 
it will get merged into tree someday :-)

As a workaround, execute the following in your scheme48 session:

,open extended-numbers methods
(define-opcode-extension make-polar &make-polar)
(define-method &make-polar ((m :real) (theta :real))
           (make-rectangular (* m (cos theta))
                   (* m (sin theta))))

Now make-polar will work for this session.

Best regards,
Vadim Zborovskii