[ruby-talk:14714] Re: Why's Ruby so slow in this case?

On Sun, May 06, 2001 at 01:11:24AM +0900, Stefan Matthias Aust wrote:
> 
> I profiled the code and here's the result.
> 
>   %   cumulative   self              self     total
>  time   seconds   seconds    calls  ms/call  ms/call  name
>  24.65   255.12    255.12   101328     2.52     7.51  Object#displace
>  10.64   365.24    110.12   101328     1.09     1.63  Object#onmap
>  10.58   474.77    109.53    18949     5.78   156.36  Range#each
                                                ^^^^^^^^^^^^^^^^^^

It seems to me that your code is spending most of its time in the
range loops.  I'd try replacing the loops like

	for i in 0...count

with simpler "while" loops like

	i = 0
	while (i < count)
	   ...
	   i = i + 1
	end

I'm guessing Range allocates a new array of indices for each loop.
Kind of wasteful, especially if it's being many times over again,
don't you think?

David S.

>   7.01   547.27     72.50   101328     0.72     0.97  Object#even
>   5.73   606.56     59.29    92238     0.64     0.90  Object#xytoh
>   4.53   653.49     46.93   110044     0.43     0.55  Object#htoy
>   4.49   699.92     46.44   110044     0.42     0.55  Object#htox
>   4.36   745.02     45.10   116328     0.39     0.50  Hex#iswater
>   3.99   786.30     41.28   299016     0.14     0.14  Fixnum#>=
>   3.88   826.45     40.15   320307     0.13     0.13  Array#[]
>   3.62   863.95     37.50   304378     0.12     0.12  Fixnum#+
>   2.65   891.41     27.47   199575     0.14     0.14  Fixnum#<
>   2.48   917.11     25.69   220668     0.12     0.12  Fixnum#==
>   2.28   940.71     23.61    24975     0.95    38.81  Object#offshore
>  ...
>