SPOT: A DSL for Extending Fortran Programs with Metaprogramming

Algorithm 13

The Fortran program for calculating the value of Pi.

(1)  program CalculatePI

(2)   integer n, i

(3)   real*8 t, x, pi, f, a

(4)   f(a) = 4.d0 /(1.d0 + a*a)

(5)   pi = 0.0d0

(6)   n = 100000

(7)   t = 1.0d0/n

(8)   do  i = 1, n

(9)        x = t  *  (i  −  0.5d0)

(10)      pi = pi + f(x)

(11)   end do

(12)   print ^*, "The value of pi is ", pi

(13)  end