Random unique numbers

[Peidus]

I hope this is the correct place to post this but I really do need help.

I need to write a programm for excel vba and since we just now started to learn how to write code in vba im having issues. This is how it has to work:
I click on a button which generates 7 unique numbers(5 in a range of 1-50 and 2 in a range of 1-8) and puts them in textbox.

I've tried searching for a solution since this has been asked a thousand times I assume but the ones i've found seems really difficult so I havn't been able to replicate any of them. Any help would be highly appreciated.

[stnkynts]

Most of us here try not to give the exact answers for what would appear to be homework problems. You can derive the answer on your own at Chip Pearsons site: http://www.cpearson.com/excel/randomnumbers.aspx

[mikerickson]

The logic that I like for non-duplicating random selection is:

To choose 2 random numbers between 1 and 8, without duplication:

1) Create an array of the numbers 1 - 8 such that myArray(n) = n
2) randomly re order that array

for n from 1 to 8
swap myArray(n) with myArray(random)
next n

3) choose the first two numbers in the reordered array.

[Peidus]

So far I know how to generate the random number but how to check if it's unique is beyond me. Also should I put the random number code into a loop that goes 5 times?

[YasserKhalil]

try this code it may help you
the code generates unique numbers between 1 and 30

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[Peidus]

Could you explain it abit more please, I am really new at this. I don't understand how your if loop works.

You do the randbetween function and you give the value that you get from that to variable c. Variable r is just used for moving so the numbers don't overlap but how does if not b(c) check for uniques?

[YasserKhalil]

Look I have this code because I need that issue before . I'm not the author of the code
Does it help you? If so you will find some dude to help how it works

[mikerickson]

the way that the Rand code in post #5 works is that when a number (c) is chosen the value of the array b(c) is set to True.
Before putting a new C into the "chosen pile" it checks to b(C) to determine if it has already been chosen.

The flaw in that is that when you get to the last number, it loops and loops and loops and .... until finally RandBetween() returns the last number.
Thats a lot of useless looping.

That code puts 1-30 in B1:B30 in random order.
using the swap approach, this code will loop 60 times (30 times to make the array 1-30, 30 time to re-order it)

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The loop count of the checking approach in Rand varies but testing shows it averages over 100 loops per run.