How to generate unique random numbers

Hi All,
I am wondering whether there is already a random library or built-in function available in Java to produce some random numbers between certain ranges that are not repetitive. Let's look at a common examples as follows:
Random diceRoller = new Random();
for (int i = 0; i < 10; i++) {
int roll = diceRoller.nextInt(6) + 1;
System.out.println(roll);
}My understanding from this approach is that it allows the same number to be repeated over and over again. However, I would like to find out how to continue generating random numbers from remaining ones that haven't been generated earlier.
Using the above example to illustrate my intention:
1st random number generated - possibility of 1 - 6 showed up. Say 5 is picked.
2nd random number generated - possibility of 1, 2, 3, 4, 6 only. Say 2 is picked.
3rd random number generated - possibility of 1, 3, 4, 6 available. Say 1 is picked.
4th random number generated - possibility of 3, 4, 6 left. Say 6 is picked.
5th random number generated - possibility of 3, 4 remains. Say 4 is picked.
Any assistance would be much appreciated.
Many thanks,
Jack

htran_888 wrote:
Hi All,
I am wondering whether there is already a random library or built-in function available in Java to produce some random numbers between certain ranges that are not repetitive. Let's look at a common examples as follows:
Random diceRoller = new Random();
for (int i = 0; i < 10; i++) {
int roll = diceRoller.nextInt(6) + 1;
System.out.println(roll);
}My understanding from this approach is that it allows the same number to be repeated over and over again. However, I would like to find out how to continue generating random numbers from remaining ones that haven't been generated earlier.
Using the above example to illustrate my intention:
1st random number generated - possibility of 1 - 6 showed up. Say 5 is picked.
2nd random number generated - possibility of 1, 2, 3, 4, 6 only. Say 2 is picked.
3rd random number generated - possibility of 1, 3, 4, 6 available. Say 1 is picked.
4th random number generated - possibility of 3, 4, 6 left. Say 6 is picked.
5th random number generated - possibility of 3, 4 remains. Say 4 is picked.
Any assistance would be much appreciated.If it is your school assignment then you have the answer above (List & the lists length).
(You might want to look at Collections)

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Hello,
I am trying to generate multiple random numbers between a given set of numbers (1-52) and not have the same number generated twice within that set. I can compare the last and next numbers with the compare function but how would I go about comparing all of the generated numbers without using a huge list of shift registers...
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Solved!
Go to Solution.

Here is an implementation of Jason's solution.
steve
Help the forum when you get help. Click the "Solution?" icon on the reply that answers your
question. Give "Kudos" to replies that help.
Attachments:
random.vi ‏10 KB

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Message was edited by: jaxjason

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public void loadList(int s, int e){
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public void printList5(){
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How to generate unique numbers

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semi-sudo code goes here
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Message Edited by altenbach on 04-12-2010 09:13 PM
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How to generate a random number with at least 6 digits?

Hi all,
All is in the question. :-)
I would like to generate a random number but the function "random
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Do you know an algorithm to generate a random number of 6 or more
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It's simple. Use 2 random number functions in the same process. Now you
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Louis.
P-F wrote in message
news:[email protected]..
> Hi all,
>
> All is in the question. :-)
>
> I would like to generate a random number but the function "random
> number" in Labview isn't accurate enough.
>
> Do you know an algorithm to generate a random number of 6 or more
> digit?
>
> Thanks,
>
> PF

How to generate pseudo random noise(PRN) binary sequence using shift registers?

what is the block diagram to generate pseudo random noise (PRN) binary sequence of 1's and 0's using shift registers
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This is a fairly simple homework problem. My hints (on the LabVIEW side):
1- look at while loops
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3-look at the logic components, AND, OR XOR
Look at this wiki article: http://en.wikipedia.org/wiki/Linear_feedback_shift_register
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Know that creating a PRN with a reasonable number of shift register taps produces very pseudo results, as the "random" pattern begins to repeat pretty quickly, thereby making it not a truly random number.
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Putnam
Certified LabVIEW Developer
Senior Test Engineer
Currently using LV 6.1-LabVIEW 2012, RT8.5
LabVIEW Champion

How to generate unique random numbers

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