--- On Fri, 17/7/09, Miranda Kim <[email protected]> wrote:
I have three variables that hold coefficients for
polynomials (such that each row contains three coefficients
for a simple polynomial y=a+bx+cx^2). I want to draw all
polynomials (10 rows) on the same graph.
Then (if possible) I have three variables that hold three
points that lie on the graph (each row contains three points
that lie on the polynomial that is defined by the
coefficients on that row), I’d like to plot these too (on
the same graph).
Does this solve your first question?
*-------------- begin example -------------------
input a b c
1 2 3
2 3 4
end
twoway function y = a[1] + b[1]*x + c[1]*x^2, ///
range(-3 3) || ///
function y = a[2] + b[2]*x + c[2]*x^2, ///
range(-3 3)
*---------------- end example -------------------
I don't understand the data structure involved in
your second question: a point on that curve should
be defined by two values: and x coordinate and a
y coordinate. If you have those you can use
-scatter- as an overlay plot within the example
I gave above. You could also consider the
-xline()- or -yline()- options.
Hope this helps,
Maarten
-----------------------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany
http://home.fsw.vu.nl/m.buis/
-----------------------------------------
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