Splitting a dataset into multiple datasets

[nick garza]

Hey all,

Newish to STATA - longtime SAS user - sorry for the basic question. I have a dataset of cases and controls. Trying to split them into two datasets based on the value of the variable casecontrol. It would be something like this in SAS:

data cases controls; set have;
if casecontrol=1 then output cases;
if casecontrol=2 then output controls;
run;

I guess I am confused since we dont have to specify datasets in STATA - so it seems like if I keep cases - then I lose the controls?

Am I missing something?

Thanks!

nick

[Ken Chui]

Welcome to Statalist!

Preserve and restore can probably do that:

use case_control, clear

preserve
keep if casecontrol == 1
save cases, replace
restore

preserve
keep if casecontrol == 2
save controls, replace
restore

Also, use works with if as well:

use case_control if casecontrol == 1, clear
save cases, replace

use case_control if casecontrol == 2, clear
save control, replace

Frame may also be an alternative. To learn more, use command help frames_intro. And for even some more ways (including external package savesome), see this link: https://www.stata.com/support/faqs/d...ts-of-dataset/.

[nick garza]

Thanks Ken!

Sorry for all the newbie questions - but I am importing my dataset from an excel file. So one of the issues I am having is I don't know what to name my dataset - is there a way to name it? Would I use that save command first?

Thanks

[Rich Goldstein]

h save

and, within the rules of your OS, choose your own file name