RosettaCodeData/Task/Pi/Fortran/pi-2.f

49 lines
1.4 KiB
Fortran

!================================================
program pi_spigot_unbounded
!================================================
do
call print_next_pi_digit()
end do
contains
!------------------------------------------------
subroutine print_next_pi_digit()
!------------------------------------------------
use fmzm
type (im) :: q, r, t, k, n, l, nr
logical :: dot=.false., init=.false.
save :: q, r, t, k, n, l
if (.not.init) then
q=to_im(1)
r=to_im(0)
t=to_im(1)
k=to_im(1)
n=to_im(3)
l=to_im(3)
init=.true.
end if
if (4*q+r-t < n*t) then
write(6,fmt='(i1)',advance='no') to_int(n)
if (.not.dot) then
write(6,fmt='(a1)',advance='no') '.'
dot=.true.
end if
flush(6)
nr = 10 * ( r - n*t )
n = 10 * ( (3*q + r) / t - n )
q = 10 * q
r = nr
else
nr = (2*q + r) * l
n = ( (q * (7*k + 2) + r*l) / (t*l) )
q = q * k
t = t * l
l = l + 2
k = k + 1
r = nr
end if
end subroutine
end program