From: Eric Hodel <drbrain@...7.net>
Date: 2006-11-29T04:13:52+09:00
Subject: Re: rand random. You've got to be kidding

On Nov 28, 2006, at 1046 , Smgspices@aol.com wrote:

>> In a message dated 11/28/2006 11:08:19 A.M. US Mountain Standard Tim,
>> brabuhr@gmail.com writes:
>>
>>>  Surely it must be possible to initialize rand with current date  
>>> and  time.
>>> Documents seem to indicate this is done with rand(0) or srand   
>>> with no value. I
>>> have tried both methods and I get the same tired old  sequence of  
>>> numbers. I
>>> would write my own random number generator  except I don't know  
>>> how to get a
>>> numeric value out of Time.
>>
>> Can  you post the code that isn't working for you?

Please quote your replies correctly.

> I was running the following in SciTE
> class Dominoes
> attr_writer :deck
> def  initialize(number)
> @deck= Array.new
> 0.upto(number)  {|i| 0.upto(i) {|j| @deck.push([i, j])}}
> end
>
> def  shuffle!
> @deck = @deck.sort{rand}

You want @deck = @deck.sort_by { rand }

> p  @deck
> end
> end
>
> a=Dominoes.new(6)
> a.shuffle!
>
> The p @deck was added so I could see what was being done.
>
> Every time I press F5 I get exactly the same result:
> [[6, 6], [4, 4], [0, 0], [5, 0], [1, 1], ...
> I get the same results if I wait a few minutes or come back the  
> next day. I
> get exactly the same results when I use fxri and freeRIDE. I am  
> running Ruby
> version 1.18.4.

Try:

10.times do puts rand end

then:

srand Time.now.to_i

10.times do puts rand end

-- 
Eric Hodel - drbrain@segment7.net - http://blog.segment7.net
This implementation is HODEL-HASH-9600 compliant

http://trackmap.robotcoop.com