This has been very well explained, but the question
about documentation remains. It is documented
e.g. in Roger Newson's tip
SJ-4-4 dm0008 Stata tip 13: generate and replace use the current sort order
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . R. Newson
Q4/04 SJ 4(4):484--485 (no commands)
tips for using generate and replace, which use the
current sort order
and it is mentioned in the FAQs. It is, as far as I know, not explicit
in the manuals, but I'd welcome a counter-example.
Another way to appreciate the point is to try to imagine how -sum()-
would work if Stata did not follow the current sort order.
Nick
n.j.cox@durham.ac.uk
Sergey Chernenko
> Is the following behavior of -replace- documented anywhere?
>
> . set obs 10
> obs was 0, now 10
> . gen x = _n
> . replace x = x - x[1]
> (1 real change made)
> . fl
> +------------+
> | x |
> |------------|
> 1. | 0 |
> 2. | 2 |
> 3. | 3 |
> 4. | 4 |
> 5. | 5 |
> |------------|
> 6. | 6 |
> 7. | 7 |
> 8. | 8 |
> 9. | 9 |
> 10. | 10 |
> +------------+
>
> I would have expected -replace- to subtract 1 from each
> observation, not
> just the first one.
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