[Chicken-users] arithmetic error in mapm egg

[Cs. Henk]

Hi!

On my linux-2.6 box with chicken-1.70 and mapm-4.9.2 the following code:

(require 'mapm)
(display (apm->integer-string 
  (apm/ (apm- (apm-expt (apm 7) (apm 19)) mm-1) (apm 6))))
(newline)

produces 1899815864228856. (In a clearer notation, a'la python/ruby:
(7**19 -  1)/6 is calculated; it's value is 1899815864228857.)

Note that coding it directly in C++:

#define NULL 0
#include <m_apm.h>
#include <stdio.h>
#include <stdlib.h>

int main(void) { 
 MAPM a = 7;
 MAPM r;
 char obuf[64];

 r = (a.ipow(19)-1)/6;
 r.toString(obuf,50);

 printf("%s\n",obuf);
}

gives the correct value.

Csaba