From: Rob Biedenharn <Rob@...>
Date: 2010-07-19T05:04:36+09:00
Subject: Re: Search Array

On Jul 18, 2010, at 1:13 AM, Chad Weier wrote:

> I have an array which is created by reading a csv file
>
> time = CSV.parse(File.read('time.csv'))
>
> time.csv contains
>
> valuea,a,100
> valueb,b,200
> valuec,c,300
>
> I want to be able to find a particular value but I used
> time.index 'valuea' and nothing displays.
>
> I am pretty sure it is because its an array of arrays
> eg if i go puts time[0][0] it will display valuea
>
> The 2 dimensional array is what I need but I am not sure how to search
> it.
> Please help as I am very new at ruby.

There's a particular method that applies in cases like this.  You have  
an array of arrays and you want to find the first array having a given  
object as *its* first value.  This is called an "association list" and  
you can get the array you want with:

irb> time = CSV.parse(File.read('time.csv'))
=> [["valuea", "a", "100"], ["valueb", "b", "200"], ["valuec", "c",  
"300"]]
irb> time.assoc('valuea')
=> ["valuea", "a", "100"]

-Rob

Rob Biedenharn		
Rob@AgileConsultingLLC.com	http://AgileConsultingLLC.com/
rab@GaslightSoftware.com		http://GaslightSoftware.com/