From: Robert Klemme <shortcutter@...>
Date: 2007-10-30T06:45:03+09:00
Subject: Re: find the closest items in an array to a given value.

On 29.10.2007 21:19, trebor777 wrote:
> I'm searching for a light method for finding the closest items to a given
> value.
> 
> example/
> 
> 1..10
> in a range
> i give,  5.5, return  5 and 6  for example....
> 
> as i'm working with arrays, containing numbers, but with no regular step...
> it will change i think.
> example..
> 
> a = [ 1, 1.25, 2, 3, 3.5 ]
> 
> if i give 1.85, it gives me 1.25 and 2

It's crucial to know whether your sequence of values is always sorted. 
If it is, you can use #each_cons and return the pair where left is 
less-or-equal than x and right is greater-than x.

If not, you can just iterate through the array and remember the last 
match and its distance - overwrite when smaller distance.

	robert


PS: A nice task for #inject. :-)