st: How do I draw graphs of injection history for 500 drug injectors ?
Date
Thu, 29 Jan 2004 19:55:49 +0100
Hello list,
I have data on 500 drug injectors and their injection history:
- injector identificator (injectorID)
- for each injector: date of injection (date), number of injections on
that day (n_inj). For the period under study, there are between 2 and 200
days with injection(s) per injector.
In the the first step in the analysis of these data, I want to do a visual
inspection of the injection profiles.
In stata this is what I want to do:
by injectorID: graph twoway bar n_inj date,
saving(filename_based_on_injectorID)
This doesn't work because graph does not allow 'by:'
Is it a clean and easy way to do this ?
