3d polar plot
I have to do a 3d polar plot.
i.e. I have to make a 3d plot by rotating a 2d polar plot along the vertical axis.
The polar plot is of the form r=f(theta).
But the polar_plot function in sage gives me only 2d plot.
How do I get a 3D version of it?
I tried spherical_plot but it is not giving me the plot which I expect to be equivalent to the revolution surface I get from rotating the 2d polar plot along vertical axis.
Example:
show(polar_plot(sin(2*theta),theta,0,2*pi))
I wanted to plot this sin(2*theta)
function as a 3d plot, by revolving it around by it's vertical axis.
But the command
spherical_plot3d(sin(2*theta),(theta,0,2*pi),(x,0,pi))
Is not giving me that. It is giving me another shape instead.
Or Another Example: polar_plot of cos(theta)
I want to do a 3d polar plot of this to get a doughnut shape
I shall also give another example with pictures.
The following plot is what I wanted using spherical3d plot
But in sage, giving the same command is giving me this plot instead.
What command should I give in sage to get a plot like the one we get from Mathematica.Mathematica?