From: "Ara.T.Howard" <Ara.T.Howard@...>
Date: 2005-10-05T14:21:48+09:00
Subject: Re: Monitoring total memory usage?

On Wed, 5 Oct 2005, Andrew Backer wrote:

> Wow, quick responses ;)
>
> No, i don't know about PP.  I am just accustomed to having serious
> output formatting control in fortran, c & derivitives, etc. for
> printing ints, floats, hex, padding, ...  Its probably here, I just
> don't know where it is.

   harp:~ > irb
   irb(main):001:0> printf "%s\n", "foobar"
   foobar

   irb(main):002:0> printf "%b\n", 42
   101010

   irb(main):004:0> puts( '|' << ('%s' % 'foobar').center(42) << '|')
   |                  foobar                  |

all the printf modifiers, and more, are there.  class string also has many
formatting features.


> I just extend the class for each individual program.  I wrote the resize so
> I don't have to worry about what arrays I pass into the function.
> resize(n,def) just .clear's it and stuffs a bunch of 'def' in to up to size
> n.  I haven't yet writting large ruby programs, so no experience worrying
> about things.
>
> Array *index* wrapping is useful in some cases (fibonacci numbers with
> no extra assignments).  However, most of the time when I accidentially
> go past the lower bounds I would like to know since a[x-1] wasn't
> intended to set the value at a[9], but since x was zero it did.
>
> nums = [1,2,3]   # nums[-1] = 3  mums[2] = 3, nums[-2] = 2, etc
>
> 	def calc_fib(n)
> 		a = [0,1,0]
> 		for i in 2..n
> 			k = i%3
> 			a[k] = a[k-1] + a[k-2]
> 		end
> 		return a[n%3]
> 	end

   harp:~ > cat a.rb
   class Array
     alias_method '__idx__', '[]'
     def [] *a, &b
       n = a.first
       raise RangeError, "negative index <#{ n }>" if Numeric === n and n < 0
       send '__idx__', *a, &b
     end
   end

   a = []
   a << 42
   p a[0]
   p a[0, 1]
   p a[0 .. 0]
   p a[-1]


   harp:~ > ruby a.rb
   42
   [42]
   [42]
   a.rb:6:in `[]': negative index <-1> (RangeError)
           from a.rb:16

hth.


-a
-- 
===============================================================================
| email :: ara [dot] t [dot] howard [at] noaa [dot] gov
| phone :: 303.497.6469
| Your life dwells amoung the causes of death
| Like a lamp standing in a strong breeze.  --Nagarjuna
===============================================================================