st: graph hbar, over, and bar coloring

[<S.Jenkins@lse.ac.uk>]

I have -graph hbar- commands that look like


gr hbar percent ,
///
	over(period) over(agegp3) missing scale(.75) 		///
	ytitle("Percentage") ylabel(0(10)80) ytick(0(5)80)	///
	scheme(s2mono) graphregion(color(white) ) 

where period takes on 5 values, and agegp3 takes on 6 values. Nicely
plotted are the bars for each period within each age group. Ideally,
however, I would like to plot the first 3 bars corresponding to the
first 3 values of period to be shown in black, and the last 2 bars
corresponding to the last 2 values of period to be shown in grey.

Simply adding a -bar(#, color(..))- option to the command does not
produce what I want. Suggestions please.  Or is it not possible to
combine barcolor options as I wish when -over()- options are also used?

I've looked in Michael Mitchell's book, 2/e, section 5.8. on changing
the look of bars, and this suggests to me that I need to define
"percent" separately for different values of period (say percent1 and
percent2). E.g.
gen percent1 = percent if inlist(period, 1, 2, 3)
gen percent2 = percent if inlist(period, 4, 5)
However when I did this (-gr hbar percent1 percent2, ... etc....) there
was no colour change as I'd hoped, and the bars were thinner.

For similar issues, cf.

. sysuse auto, clear
(1978 Automobile Data)

. gr hbar weight, over(foreign)

. gr hbar weight, over(foreign) bar(1, color(black)) bar(2, color(gs8))

I would have hoped that the bar coloring would cycle within the over
group, but it doesn't.


Stephen
------------------
Stephen P. Jenkins <s.jenkins@lse.ac.uk>
Department of Social Policy and STICERD
London School of Economics and Political Science
Houghton Street
London WC2A 2AE
United Kingdom
Tel: +44(0)20 7955 6527
Survival Analysis Using Stata:
http://www.iser.essex.ac.uk/survival-analysis
Downloadable papers and software: http://ideas.repec.org/e/pje7.html


Please access the attached hyperlink for an important electronic communications disclaimer: http://lse.ac.uk/emailDisclaimer

*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/