Re: st: vertical lines between two co-ordinates in graph

[Nick Cox <njcoxstata@gmail.com>]

Here's one way to do it

gen my94 = 94
gen my0 = 0
gen x2 = 4
twoway (function y =  94              , range(0  4) )/*
 */    (function y =  x^2 + 14*x +  22, range(0 7.5) )  /*
 */    (function y = -x^2 - 10*x + 150, range(0 7.5) ) /*
 */    (rspike my94 my0 x2, legend(off))

and another

twoway (function y =  94              , range(0  4) )/*
 */    (function y =  x^2 + 14*x +  22, range(0 7.5) )  /*
 */    (function y = -x^2 - 10*x + 150, range(0 7.5) ) /*
 */    (scatteri 94 4 0 4, recast(line) legend(off))

Nick

On Thu, Sep 29, 2011 at 10:57 AM, Marco Ercolani
<m.g.ercolani@bham.ac.uk> wrote:

> Can Stata draw a vertical line between two co-ordinates of a graph? I need to do this for numerous graphs so I don't want to do it manually using a graph editor.
>
> I need a line that starts at the intersection of two curves and reaches down to the horizontal axis. For the example below, I can draw a horizontal line at y=94 for x= 0 to 4 but not the vertical line at x=4 for y= 0 to 94.
>
> twoway (function y =  94              , range(0  4) )/*
>  */    (function y =  x^2 + 14*x +  22, range(0 7.5) )  /*
>  */    (function y = -x^2 - 10*x + 150, range(0 7.5) ), /*
>  */    legend(off)

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