how do I generate random numbers

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Join Date: Oct 2006

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jamello

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how do I generate random numbers

Jul 23rd, 2008

Hello people!
I need ideas about how to randomly generate a set of integers - a set of 16 on 40 rows.
I had tried the Randomize function on the .net framework but has not been successful. Any idea woud be appreciated

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tuse

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Re: how do I generate random numbers

Jul 24th, 2008

Use the Random Class.

 Help with Code Tags 
 asp.net Syntax (Toggle Plain Text) 
 
 
            Dim arbit As New Random
            Randomize()
 
X:          For i = 0 To a.GetUpperBound(0)
                t = arbit.Next(1, 10)
 
            ' Generate between the numbers 1 and 10
 
                If Array.IndexOf(a, t) = -1 Then
                    a(i) = t
 
                Else
                    GoTo X
                End If
 
            Next
 
 

            Dim arbit As New Random
            Randomize()

X:          For i = 0 To a.GetUpperBound(0)
                t = arbit.Next(1, 10)

            ' Generate between the numbers 1 and 10

                If Array.IndexOf(a, t) = -1 Then
                    a(i) = t

                Else
                    GoTo X
                End If

            Next

Here I am filling an array with random numbers. Note that I have used the goto statement so ensure that unique numbers are inserted into the array. (Avoiding Duplicates)

My blog on .NET- http://dotnet.tekyt.info

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jamello

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Re: how do I generate random numbers

Jul 25th, 2008

tuse,
thanks for your reply. Yes that is a good idea, but if i fill the first line with 16 integers (aided by an array) I would want the next group of 16 to be unique as a group. So if I generate 1000 of such group of 16 integers no group would apear twice. I hope the challenge is clearer.

Thanks

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tuse

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Re: how do I generate random numbers

Jul 25th, 2008

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Originally Posted by jamello

tuse,
thanks for your reply. Yes that is a good idea, but if i fill the first line with 16 integers (aided by an array) I would want the next group of 16 to be unique as a group. So if I generate 1000 of such group of 16 integers no group would apear twice. I hope the challenge is clearer.

Thanks

Do you mean the uniqueness of the numbers should be restricted to a group of 16 or do you want 16 x 40 unique numbers

--------------------

Yeah I got what you are trying to say.

Last edited by tuse : Jul 25th, 2008 at 1:06 pm. Reason: Eureka!

My blog on .NET- http://dotnet.tekyt.info

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Re: how do I generate random numbers

Jul 25th, 2008

Can you tell me the range in which you need these integers?

I have something in mind which depends upon this.

My blog on .NET- http://dotnet.tekyt.info

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jamello

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Re: how do I generate random numbers

Jul 25th, 2008

Yes,
the integers naturally would be 0 to 9 for the groups.
i mean something like this

Help with Code Tags

(Toggle Plain Text)

1.  8937474633290944
2.  8464595950698568
3.  0734736478237473
...
40 9689896859895596

get it?
peace

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Originally Posted by tuse

Can you tell me the range in which you need these integers?

I have something in mind which depends upon this.

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Join Date: Jul 2007

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tuse

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Re: how do I generate random numbers

Jul 25th, 2008

Try this-

Just generate 16 x 40 numbers random numbers using the code. If you want it in the range as said, find the remainder of the generated random numbers on division by 10. Then split this one dimensional array into the matrix you need.
------
Hopefully you will get as you need.

But by no means is this the best way to go. There might (must) be a better way.

------
Are you using this for an online test application?

Last edited by tuse : Jul 25th, 2008 at 1:43 pm. Reason: Saw the previous post

My blog on .NET- http://dotnet.tekyt.info

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jamello

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Re: how do I generate random numbers

Jul 25th, 2008

No no i am not using this for an e-testing software.
Thanks all the same tuse. You are a great guy

U know talking about another way, I had this idea of generating guids then picking out 16 characters and then changing the alphabets to their numeric equivalents. Then save the results in a database table with the number being the primary key trusting the database to throw out duplicates if any.
Now how's that
what's your take?

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Originally Posted by tuse

Try this-

Just generate 16 x 40 numbers random numbers using the code. If you want it in the range as said, find the remainder of the generated random numbers on division by 10. Then split this one dimensional array into the matrix you need.
------
Hopefully you will get as you need.

But by no means is this the best way to go. There might (must) be a better way.

------
Are you using this for an online test application?

Last edited by jamello : Jul 25th, 2008 at 2:22 pm.

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prasu

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Re: how do I generate random numbers

Jul 25th, 2008

Since you want to create 40 unique groups where within a group a number may repeat.
Create a array of string and every time a group is created store that as a string.
Just compare the contents of the string with the newly created group. if they are the same abandon it else enter it as the 'n+1'th element of the array.
Thus you will get 40 groups which are unique.