st: RE: Using variables in numlist of forvalue command

["Nick Cox" <n.j.cox@durham.ac.uk>]

You can't put a variable into a numlist
in this way. 

Try something like 

su daysupply, meanonly 
forvalues daynum = 2/`r(max)' { 
	replace date`daynum' = date1 + `daynum' - 1 if `daynum' <= daysupply 
} 

You may know the maximum in advance, so that you 
can simplify to say 

forvalues daynum = 2/10 { 
	replace date`daynum' = date1 + `daynum' - 1 if `daynum' <= daysupply 
} 

Nick
n.j.cox@durham.ac.uk 

Shawn.Fultz@med.va.gov

I'm trying to change several variables in each observation. The problem is that the number of variables I want to update is different for each observation and this number is a variable in that observation. I've tried using a forvalues loop, which works if I specify a stop and start number, but I cannot find a way to put a variable in the numlist allowing this to change for each observation.

Here's the command that works:
        forvalues daynum = 2/10 {
        replace date`daynum'=date1+`daynum'-1
        }

But when I replace the 10 with the variable that tells me how many date variables to change, I get a syntax error.
        forvalues daynum = 2/daysupply {
        replace date`daynum'=date1+`daynum'-1
        }

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