From: William James <w_a_x_man@...>
Date: 2009-02-11T17:59:05+09:00
Subject: Re: Ruby vs Perl performance

Reid Thompson wrote:

> William James wrote:

> > 
> > Using the functional language F#:
> > 
> > 0.0400575999999999 on my laptop with 2GHz Pentium.
> > 
> 
> On same box using all C.
> Echo delay is 0s and 20842us -> 20842 microseconds = 0.020842
> seconds.  This is an Intel(R) Core(TM)2 CPU 6320  @ 1.86GHz box w 2GB
> RAM running gentoo with entire system compiled with
> CFLAGS="-march=prescott -O2 -g -pipe" + feature splitdebug (
> everything compiled with debug except mandInC ).  -rwxr-xr-x  1
> rthompso staff         7104 2009-02-10 23:36 mandInC

To make timing more accurate, let's calculate the set 100 times
but draw it only 1 time.

Result:  1.99286559999999  (laptop with 2GHz Pentium M)


(**  Note that bailout has been changed.  **)
let bailout = 4.0
let max_iterations = 1000


let iterate ci cr =
  let rec loop zi zr i =
    if i > max_iterations then
      0
    else
      let temp = zr * zi  and
        zr2 = zr * zr  and
        zi2 = zi * zi  in
      if zi2 + zr2 > bailout then
        i
      else
        loop (temp + temp + ci) (zr2 - zi2 + cr) (i + 1)
  in
  loop 0.0 0.0 1

let mandelbrot n =
  for y = -39 to 38 do
    if 1 = n then  print_endline ""  else ();
    for x = -39 to 38 do
      let i = iterate
        (float x / 40.0) (float y / 40.0 - 0.5) in
      if 1 = n then
        System.Console.Write( ( if 0 = i then "*" else " " ) )
      else ();
    done
  done;;


let start_time = Sys.time () in
for iter = 1 to 100 do
  mandelbrot iter
done;
print_endline "";
System.Console.Write (Sys.time () - start_time);
print_endline "";