Help on performing calculations on formula results

[AussieExcelUser]

I need to apply the "RANDBETWEEN" function to a formula result in a cell
and am having difficulty. I can get the following formula to work by
using the "Iteration" function set to 1 but get erratic results,
including values added to cells where there were no values as a result
of the Lookup:

"=if(if(isna(vlookup($A$1,sheet2!A$1$:B$1,2,false)),"0",vlookup($A$1,sheet2!A$1$:$B$1,2,false))>30,RANDBETWEEN(20,30),A1)"

What I want to do is generate a random number between 20 and 30 if the
result of the lookup is greater than 30. The lookup can result in
values from negative 500 through to postive 500.

Any help would be appreciated as this is driving me nuts and costing a
lot of development time.

 

[Max]

In say, Sheet1,

Try something like this in B1:
=IF(A1="","",IF(ISNA(VLOOKUP(A1,Sheet2!A:B,2,0)),0,
IF(VLOOKUP(A1,Sheet2!A:B,2,0)>30,RANDBETWEEN(20,30),A1)))

where A1 will hold an input to lookup

If A2, A3, etc holds yet other inputs,
the formula in B1 can be copied down "as-is" to return corresponding values

 

[AussieExcelUser]

Thanks for your input Max, much appreciated. The only issue is that I
need everything to be done in the one cell. The lookup returns the
first value and then I need to apply the random number generator if the
result of the lookup is greater than 30. I cannot insert a column
adjacent to perfom part of the query and give a result as I am working
on a number of large and different sized tables on a sheet, some with
merged cells etc. and can only show one value per item.

I have tried hidden colums and other ways to overcome this issue, but
they played havoc for the end users of the reports when printed etc.

 

[Max]

Thanks for your input Max, much appreciated. The only issue is that I
need everything to be done in the one cell. The lookup returns the
first value and then I need to apply the random number generator if the
result of the lookup is greater than 30. I cannot insert a column
adjacent to perfom part of the query and give a result as I am working
on a number of large and different sized tables on a sheet, some with
merged cells etc. and can only show one value per item.

I have tried hidden colums and other ways to overcome this issue, but
they played havoc for the end users of the reports when printed etc.

Think I'm out of ideas here, sorry.
Perhaps others would drop by and offer you their insights
(maybe a vba solution is available ?)
Hang around awhile ..

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