From: "David A. Black" <dblack@...>
Date: 2009-02-13T22:02:31+09:00
Subject: Re: How to retrive first 10 items from hash in ruby?

Hi --

On Fri, 13 Feb 2009, Bertram Scharpf wrote:

> Hi,
>
> Am Freitag, 13. Feb 2009, 21:08:19 +0900 schrieb Dave Baldwin:
>>
>> On 13 Feb 2009, at 11:04, Vikas Gholap wrote:
>>
>>> I want to retrieve first 10 items(key value pairs) from given hash{}
>>>
>>> hashTable.sort {|a,b| -1*(a[1]<=>b[1])}
>>
>> You need to save the results.
>> ary = hashTable.sort {|a,b| -1*(a[1]<=>b[1])}
>>
>> ary[0, 10] will return an array of the first 10 entries
>>
>> ary[0, 10].each {|e| puts  "Key: #{e[0} ==> #{[e[1]}"
>
> As ary is only of temporary use, you don't need to create another
> array ary[0,10]. I suggest:
>
>  10.times { puts "Key: %s ==> %s" % e.shift }

Do you mean ary.shift?

>  e.clear  # optional

You can also save on shifts like this:

   10.times {|i| # do something with ary[i] }


David

-- 
David A. Black / Ruby Power and Light, LLC
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