RE: Re: st: Plotting several polynomials on the same graph

[David Airey <david.airey@vanderbilt.edu>]

.

Dang. That is tricky! Nice. I had this same problem and question today  
and got as far as your first solution. Thanks for this second solution.

-Dave

> --- Miranda wrote:
> > I wondered if there is any way of adding functions onto the same  
> graph
> > using a separate command (on a separate line), so as to be able to  
> loop
> > over these and superimpose several (i.e. instead of using the '||'  
> in
> > the 'twoway' command)
>
> The trick is to create the graph command in a loop while storing it in
> a local macro, like in the example below:
>
> *---------------- begin example -------------------
> input a b c
> 1 2  3
> 2 3  4
> 1 2 -3
> 2 3 -4
> end
>
> forvalues i = 1/4 {
> 	local gr "`gr' function y = a[`i'] + b[`i']*x + c[`i']*x^2"
> 	local gr "`gr', range(-3 3) ||"
> }
>
> twoway `gr'
> *--------------- end example ----------------------
>
> Hope this helps,
> Maarten
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