program Fibonacci3 * (Fibonacci) * Print ascending members of the Fibonacci sequence that are * representable as 64-bit signed integers, prefixed by their term * numbers, and followed by the ratio of successive terms, to * demonstrate the 1.618...^n growth (the ratio approaches the golden * ratio, (1 + sqrt(5))/2 = 1.6180339887498949, and reaches it (to * machine precision) at 41 terms: the fourth item on each line is * the difference from the golden ratio). * (19-Apr-2002) character*1 TAB parameter (TAB = char(9)) * double precision GOLDEN_RATIO double precision ratio integer*8 lo, hi, n * GOLDEN_RATIO = (1.0d0 + sqrt(5.0d0))/2.0d0 * lo = 1 hi = 1 n = 1 write (6,'(i2,a,i19)') n, TAB, lo do while (hi .GT. 0) n = n + 1 ratio = dble(hi)/dble(lo) write (6,'(i2,a,i19,a,f19.15,a,f19.15)') n, TAB, hi, TAB, X ratio, TAB, (ratio - GOLDEN_RATIO) hi = lo + hi lo = hi - lo end do * end