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\section*{Matlab test}
This is rudamentary test of Matlab.  We'll just test simple things like this:
\begin{Matlabcode}
x = [1 2 3 4 5];
y = [6 6.5 7 7 6.5];
z = x + y
\end{Matlabcode}
We can also see how plots come out.  This one is the default $6\times6$ size in pdf format, scaled to $\frac13$ of that:
\begin{Matlabcode}{fig, dispw=2in}
plot(x,y);
\end{Matlabcode}
\\
The Matlab people really should change the way they scale plots so that the plotted data don't run up against the edges like that.

This is a different plot, constructed to be 4 inches by 3 inches, PNG format:
\begin{Matlabcode}{fig, width=4in, height=3in, figfmt=png}
plot(x,z);
\end{Matlabcode}



\end{document}