st: added line in front of area shading

[Roger Harbord <roger.harbord@bristol.ac.uk>]

I'm using a command that produces something similar to:

. twoway lfitci mpg headroom , yline(20)

However I want the added line to go in front of the shaded area, not behind 
(because in my real graph i truncate the CI if it crosses the reference line 
so the reference line then forms the boundary, so it looks silly if it 
disappears - the real graph uses twoway rarea but this gives the idea).

After looking at -help added_line_options- I assumed that

. twoway lfitci mpg headroom , yline(20, lstyle(foreground))

- might do the trick, but no luck.

Clearly I can do something like

. gen refline = 20
. twoway lfitci mpg headroom || line refline headroom, clstyle(foreground)
. drop refline

- but then the line only extends over the range of the data, not the range of 
the x-axis (in my real example it looks worse).

(Apologies if this has been asked before on Statalist - i have a very vague 
memory that it might have been but I had a look in the archives and couldn't 
find anything.)

Thanks,
Roger.
----------------------------------------------------
Roger Harbord     mailto:roger.harbord@bristol.ac.uk
Department of Social Medicine, University of Bristol

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