Re: st: finding the max of a variable and then using it

[Maarten buis <maartenbuis@yahoo.co.uk>]

--- On Tue, 10/8/10, Data Analytics Corp. wrote:
> I have a data set with a variable called opp_price. 
> I'd like to find the maximum value for opp_price (I would
> imagine I'd use
> 
> egen opp = max(opp_price)
> 
> or something like this, but then use this single value in
> subsequent graphing statements like the following:
> 
> xline(opp, lwidth(thin))
> text(0.0 238 "OPP: $opp", place(w))
> 
> Of course this doesn't work since opp is a new variable
> with as many observations as opp_price.  I need a
> scalar that I can then use in subsequent statements. 
> Can anyone help?

The easiest way to do this is to store the maximum in a 
local macro (see -help macro-, also click through to the
extended macro function, especially the display function
may prove useful in your case). Also see the example 
below:

*---------------- begin example ------------
sysuse auto

sum mpg, meanonly
local max = r(max)

scatter price mpg, ///
    xline(`max')   ///
    text(0 `max' "`max'", place(w))
*---------------- end example --------------
(For more on examples I sent to the Statalist see: 
http://www.maartenbuis.nl/example_faq )

Hope this helps,
Maarten

--------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany

http://www.maartenbuis.nl
--------------------------


      

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