/*
** euclid.src
** Author: Alan G. Isaac
**         mailto:aisaac@american.edu
** Date:   28 June 2000
** Caveat: this code is provided gratis but without
**         any performance warrantee or guarantee
**
**> euclid
**
**  Purpose:    find greatest common denominator of the
**              largest and smallest elements of a matrix
**
**  Format:     x = euclid(mn);
**
**  Input:      mn    matrix
**
**  Output:     x     the greatest common denominator of the
**                    largest and smallest elements of a matrix
**
**  Comments:   uses only integer part of mn
**
*/
proc (1) = euclid(mn);
  local m,n,r;
  mn=vec(mn);
  mn=abs(int(maxc(mn)|minc(mn)));
  m=maxc(mn);
  n=minc(mn);
  r=m%n;
  do while r/=0;
  m=n;
  n=r;
  r=m%n;
  endo;
retp(n);
endp;