data already long..variable yydx already exists

[Martin Imelda Borg]

Hi I'm trying to use Paul Dickman's code

Source:
https://pauldickman.com/software/sta...e-standsurv.do

However when I come to this section
- The only thing I have tweaked is keeping yydx here - as I think it makes sense to keep it as it is then used to reshape

//reshape from wide to long to make plotting easier
keep in 1
keep id S_male* S_female* S_diff* yydx
reshape long S_male S_male@_lci S_male@_uci S_female S_female@_lci S_female@_uci S_diff S_diff@_lci S_diff@_uci, i(id) j(yydx)

I get the following error

variable yydx already exists
Data are already long.
r(110);

Any thoughts why this is happening?

[Clyde Schechter]

Any thoughts why this is happening?

It's happening for exactly the reason that Stata's error message tells you: yydx already exists. The name specified in the -j()- option of -reshape long- must be a new variable, not an existing one.

I'm inferring from your code that the variables S_male, S_female, S_diff, and their corresponding _uci and *_lci variables are indexed by some number and you would like to change the organization to just single variables S_male, S_female, S_diff, S_uci, and S_lci, with that index number as a separate variable. You just have to pick a name for that variable, preferrably a descriptive one like "visit number" or "age_group" or whatever that is, and then put that name in the -j()- option. There is probably no need to mention yydx in the command at all.