print agm(1, 1/sqr(2))
print agm(1,1/2^.5)
print using("#.############################",agm(1, 1/sqr(2)))

function agm(agm,g)
 while agm
   an  = (agm + g)/2
   gn  = sqr(agm*g)
   if abs(agm-g) <= abs(an-gn) then exit while
   agm = an
   g   = gn
 wend
end function