View Single Post
  #6   Report Post  
Posted to microsoft.public.excel.worksheet.functions
Joe User[_2_] Joe User[_2_] is offline
external usenet poster
 
Posts: 905
Default random integer with sum constraint

"Karin" wrote:
I want to generate two random integers that fall within a certain range
("min" to "max", e.g. 0 to 10) AND that sum to equal no more than a
given value ("maxsum", e.g. 19)

The first integer is easy (using a Analysis Toolpak add-in)
A1=RANDBETWEEN(min, max)


That presumes min+max <= maxsum. If that assumption is valid in your case,
fine. Otherwise, I think you should write:

A1: =RANDBETWEEN(min, MIN(max, maxsum-min))

Example: if min=1, max=1000 and maxsum=50, random integers from 50 through
1000 are not valid.


But that second integer has me stuck. I started with
A2=RANDBETWEEN(min, maxsum-A1)


That should be:

A2: =RANDBETWEEN(min, MIN(max,maxsum-A1))


----- original message -----

"Karin" wrote in message
...
Hi

I want to generate two random integers that fall within a certain range
("min" to "max", e.g. 0 to 10) AND that sum to equal no more than a given
value ("maxsum", e.g. 19)

The first integer is easy (using a Analysis Toolpak add-in)
A1=RANDBETWEEN(min, max)

But that second integer has me stuck. I started with A2=RANDBETWEEN(min,
maxsum-A1) but then a lot of the results were larger than "max." Oops. Any
ideas on what else I need to put in there?

Thanks,
Karin