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From: Reiichi Tyrael on 1 Mar 2010 14:21
I must create a little game; the one who play it must choose 2 numbers,
the beginning and the end of a range, and the program generate a secret
random number within that range, so the player must guess it!
But the problem is...how do I generate a random number?
I though at something like this:

number_to_guess = rand(n1..n2)

but it give me the error message "in `rand': can't convert Range into
Integer (TypeError)"

What can I do? Thanks!
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From: David Springer on 1 Mar 2010 14:35
Reiichi Tyrael,

Is the range inclusive OR exclusive?

Should n1 OR n2 be reurned sometimes or never?

> number_to_guess = rand(n1..n2)


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From: Reiichi Tyrael on 1 Mar 2010 14:40
David Springer wrote:
> Reiichi Tyrael,
>
> Is the range inclusive OR exclusive?
>
> Should n1 OR n2 be reurned sometimes or never?
>
>> number_to_guess = rand(n1..n2)
Inclusive!

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Posted via http://www.ruby-forum.com/.

From: David Springer on 1 Mar 2010 14:55
Reiichi Tyrael wrote:

> Inclusive!

Okay, I'll assume that these are two different positive integers.

Try this:

number_to_guess = (n2 > n1) ? n1 + rand((n2-n1+1)) : n2 +
rand((n1-n2+1))
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From: Robert Klemme on 1 Mar 2010 15:32
On 01.03.2010 20:21, Reiichi Tyrael wrote:
> I must create a little game; the one who play it must choose 2 numbers,
> the beginning and the end of a range, and the program generate a secret
> random number within that range, so the player must guess it!
> But the problem is...how do I generate a random number?
> I though at something like this:
>
> number_to_guess = rand(n1..n2)
>
> but it give me the error message "in `rand': can't convert Range into
> Integer (TypeError)"
>
> What can I do? Thanks!

rand only accepts an integer which will make it produce values in the
range 0...n (exclusive). So you can do:

irb(main):001:0> low, high = 12, 56
=> [12, 56]
irb(main):002:0> r = low + rand(high - low)
=> 54

Kind regards

robert

--
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/
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