Here is my input-file:
m:matrix([100,16000],[200,8000],[500,3636],[1000,1818],[2000,870],[5000,323],[10000,160],[20000,83],[50000,33],[100000,20]);
lsquares_estimates (m, [x, y], y = sqrt(a^2 + (10e7/(2*%pi*x*b))^2),[a, b], initial=[10, 10]);
/* => [[a = 19.2898942613692, b = 9.89381119455951]]*/
/* b = 10 is the exact value for b.*/
/* I'll construct the mean square error as a function of a alone*/
/* and then plot it. */
mse : lsquares_mse (m, [x, y], y = sqrt(a^2 + (10e7/(2*%pi*x*b))^2));
mse1 (a) := ''(subst (b=10, mse));
plot2d(mse1(a), [a,0,100]);
best regards,
hugo
On Mon, 14 Jun 2010, Leo Butler wrote:
>
>
> On Mon, 14 Jun 2010, Hugo Coolens wrote:
>
> < I replaced plot2d (mse1, [a, 0, 100]); by plot2d(mse1(a), [a,0,100]);
> < but I still get the same error-message:
> < (%i5)
> < gnuplot> plot [0.:100.]'/home/coolens/maxout.gnuplot_pipes' index 0 notitle
> < with lines 3
> <
> < ^
> > <
> < > m:matrix([100,16000],[200,8000],[500,3636],[1000,1818],[2000,870],[5000,323],[10000,160],[20000,83],[50000,33],[100000,20]);
> < > < lsquares_estimates (m, [x, y], y = sqrt(a^2 + (10e7/(2*%pi*x*b))^2),[a,
> < > b],
> < > < initial=[10, 10]);
> < > < /* => [[a = 19.2898942613692, b = 9.89381119455951]]*/
> < > < /* b = 10 is the exact value for b.*/
> < > < /* I'll construct the mean square error as a function of a alone*/
> < > < /* and then plot it. */
> < > < mse : lsquares_mse (m, [x, y], y = sqrt(a^2 + (10e7/(2*%pi*x*b))^2));
> < > < mse1 (a) := ''(subst (b=10, mse));
> < > < plot2d (mse1, [a, 0, 100]);
>
> Could you show us the output of the preceding commands, beginninng with
> the line where you define m.
>
> Note, too, that you may want to upgrade your version of Maxima. The
> current version is 5.21.1.
>
> Leo
>
> --
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>
>