Summary

A depiction of the function ${\displaystyle f(r,\theta )=r\sin(2\theta )}$ around the origin.

In x, y coordinates, this function is equal to

${\displaystyle f(r,\theta )=\left\|(x,y)\right\|\sin \left(2\tan ^{-1}\left({\frac {y}{x}}\right)\right)}$

The graph was created with matlab, using the following script:

D = [-1:0.1:1];
[X Y] = meshgrid(D,D);
L=sqrt(X.^2+Y.^2);
A=atan(Y./X);
A(isnan(A))=0;
Z=L.*sin(2*A);
surfc(X,Y,Z);
view(15,40)
xlabel('x')
ylabel('y')
zlabel('f(x,y)')
axis equal
camlight headlight
lighting gouraud
print -dpng f.png
%print -depsc2 f.eps
%!pstoedit -f plot-svg f.eps f.svg
%!firefox f.svg
%!gv f.eps

If anyone now how to get an SVG file with lighting enabled out of matlab, please feel free to supersede this image with a vectorized version.

Licensing

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