* Joe Van Dyk <joevandyk / gmail.com> [0417 22:17]:
> How can I neatly iterate from 0 to some number (either pos or neg)
> while skipping over some number of numbers?
> 
> How's that for confusing?
> 
> So,
> 
> If the ending number is 550 and I want to skip by 100s, it would print
> 0, 100, 200, 300, 400, 500.
> 
> If the ending number is -552 and I want to skip by 100s, it would print
> 0, -100, -200, -300, -400, -500
> 
> There's nothing in the standard library that does this kind of thing, is there?

rasputnik$ ri Numeric#step
----------------------------------------------------------- Numeric#step
     num.step(limit, step ) {|i| block }     => num
------------------------------------------------------------------------
     Invokes block with the sequence of numbers starting at num, 
     incremented by step on each call. The loop finishes when the value 
     to be passed to the block is greater than limit (if step is 
     positive) or less than limit (if step is negative). If all the 
     arguments are integers, the loop operates using an integer 
     counter. If any of the arguments are floating point numbers, all 
     are converted to floats, and the loop is executed floor(n + 
     n*epsilon)+ 1 times, where n = (limit - num)/step. Otherwise, the 
     loop starts at num, uses either the < or > operator to compare the 
     counter against limit, and increments itself using the + operator.

        1.step(10, 2) { |i| print i, " " }
        Math::E.step(Math::PI, 0.2) { |f| print f, " " }

     produces:

        1 3 5 7 9
        2.71828182845905 2.91828182845905 3.11828182845905

rasputnik$ 

-- 
'Tempers are wearing thin. Let's hope some robot doesn't kill everybody.'
		-- Bender
Rasputin :: Jack of All Trades - Master of Nuns