From: Bertram Scharpf <lists@...>
Date: 2009-02-14T01:37:52+09:00
Subject: Re: How to retrive first 10 items from hash in ruby?

Hi,

Am Freitag, 13. Feb 2009, 23:29:05 +0900 schrieb David A. Black:
> On Fri, 13 Feb 2009, Bertram Scharpf wrote:
>>
>>  ary = hashTable.sort { |a,b| a[1]<=>b[1] }
>>  10.times { puts "Key: %s ==> %s" % ary.pop }
>
> I'd still rather walk through the array than have to coordinate the
> sort operation and a destructive array operation.
>
>   ary = hash_table.sort {|a,b| b[1] <=> a[1] }
>                  # or sort_by {|a| -a[1]}
>   10.times {|i| # ary[i] ... }

By the way: This is starting to make fun. I don't know how the
internal sort mechanism works, but maybe something like this here
would be faster?

  a = Array.new 200 do rand 0x1000 end
  h = []
  a.each { |x|
    if h.length < 10 or x > h.first then
      h.push x
      h.sort!
      h.shift if h.length > 10
    end
  }

Bertram


-- 
Bertram Scharpf
Stuttgart, Deutschland/Germany
http://www.bertram-scharpf.de