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Graphing Solids of Revolution

To accomplish this in three dimensions, we utilize the tubeplot function from the plots library of Maple, along with suitable options.

For sake of demonstration, suppose we wish to plot the surface of revolution one gets from rotating the curve tex2html_wrap_inline191 about the x-axis. Maple commands to accomplish this would be:

  > f:= x -> sqrt(x) + 1;


  > with(plots):
  > PltStyle:= axes= NORMAL, style= PATCHNOGRID, tubepoints=40;


  > tubeplot([x,0,0], x=0..9, radius=f(x),PltStyle);


The last command uses the function tubeplot from the plots library, rotating about the x-axis (as controlled by the first argument, [x,0,0], letting x range from 0 to 9, using the function f(x) to determine the radius at each point, and setting the options as set up by the line assigned PltStyle). The only especially noteworthy thing set by PltStyle is the last option, tubepoints. This effectively determines the resolution of the graph; the higher the value, the smoother it is (but the longer it takes). A value as low as 10 gives a fairly crude surface, by comparision. (Try it!)

Sean O Anderson
Tue Dec 3 12:06:23 EST 1996