How can I make a polar contour plot in Maxima? Given an expression such as
exp(-r) * cos(phi)
I'd like to plot contours in the x-y plane which have the same value of the expression at all points along the contour.
I've tried
draw3d(cylindrical(exp(-r) * cos(phi), r, 0, 5, phi, 0, 2*%pi), contour=map))
but cylindrical
plots r as a function of z and phi, not z as a function of r and phi. It would be nice to not have to convert manually to Cartesian coordinates.