Re: st: gen a newvar

[Ron�n Conroy <rconroy@rcsi.ie>]

Hans J. Baumgartner wrote:

> Dear Statalist,
>
> this may sound like a very silly question. But I seem to be unable to
> solve it anyway.
>
>
> My data looks like this:
>
> id      x
> 1       5
> 1       5
> 1       10
> 1       10
> 1       21
> 1       21
> 1       21
> 2      ...
>
> I want to generate a newvar with the maximum value of x , which is _N.
> But if the difference between the largest and the second largest value
> is <=7, newvar should take the value of the second largest value of x.
No single step solution, but

by id:gen max_x=x[_N]
by id:replace max_x=x[_N-1] if (x[_N] - x[_N-1]) <=7



--

Ronan M Conroy (rconroy@rcsi.ie) 
Senior Lecturer in Biostatistics 
Royal College of Surgeons 
Dublin 2, Ireland 
+353 1 402 2431 (fax 2764) 
-------------------- 
Just say no to drug reps 
http://www.nofreelunch.org/

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