Solved

Generate unique random numbers

Posted on 2010-08-20
7
446 Views
Last Modified: 2012-08-13
Hi,

I need something that will generate a column full of random numbers between say 1 and 50, which are unique, the number of rows to include needs to be dynamic and would prefer a formula as need to avoid vba.

Cheers
0
Comment
Question by:StormFusion
7 Comments
 
LVL 17

Expert Comment

by:calacuccia
ID: 33489388
=RAND()*50

Put this in the range you want it to be in. Everything you hit F9, it updates.

If you want only integer number, use = Int(Rand()*50)

This might not be unique though especially if you were looking for integers.
0
 
LVL 8

Expert Comment

by:jimmyray7
ID: 33489395
There isn't a built in fuction that will do the unique part (RAND() is not unique).  However, I did find a script that will do unique - http://www.ozgrid.com/VBA/RandomNumbers.htm
0
 
LVL 17

Expert Comment

by:calacuccia
ID: 33489442
Jim,

Indeed my solution gives no unique list, as mentioned, however, he mentioned to want to avoid vba. But your looks nice.

BTW: do you know Antrat, the OzGrid guy? (Dave). We used to spend masses of time together here :-)

0
DevOps Toolchain Recommendations

Read this Gartner Research Note and discover how your IT organization can automate and optimize DevOps processes using a toolchain architecture.

 
LVL 81

Accepted Solution

by:
byundt earned 500 total points
ID: 33489478
1) List the numbers 1 through 50 in A1:A50
2) Put the following formula in cells B1:B50
=RAND()
3) To pull a set of umpteen unique random numbers, use the following formula in cell C1 then copy it down:
=INDEX($A$1:$A$50,MATCH(SMALL($B$1:$B$50,ROWS($C$1:$C1)),$B$1:$B$50,0))

Each time you hit F9, you get a different selection of random numbers

For grins, the sample workbook highlights any duplicates.

Brad
UniqueRandomNumbersQ26418995.xlsx
0
 
LVL 2

Expert Comment

by:Thomas Gibson
ID: 33490598
Quick and dirty:
http://www.random.org/integers/?num=50&min=1&max=50&col=1&unique=on&base=10&format=html&rnd=new

You can decide how many columns you want it formatted in, start number, finish number.  Easier interface than Excel.
0
 

Author Closing Comment

by:StormFusion
ID: 33492221
Perfect, simple and effectively clever, cheers
0
 
LVL 81

Expert Comment

by:byundt
ID: 33493204
StormFusion,
Thanks for the kind words and grade!
Brad
0

Featured Post

DevOps Toolchain Recommendations

Read this Gartner Research Note and discover how your IT organization can automate and optimize DevOps processes using a toolchain architecture.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Approximate matching with VLOOKUP and MATCH seems to me to be a greatly under-used technique, and one which is vital for getting good performance out of large lookups. Until recently I would always have advised using an exact match for simplicity an…
Excel can be a tricky bit of software to get your head around. Whilst you’ll be able to eventually get to grips with the basic understanding of how to get by, there are a few Excel tips that not everybody will even know about let alone know how to d…
This Micro Tutorial will demonstrate in Microsoft Excel how to add style and sexy appeal to horizontal bar charts.
Many functions in Excel can make decisions. The most simple of these is the IF function: it returns a value depending on whether a condition you describe is true or false. Once you get the hang of using the IF function, you will find it easier to us…

777 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question