> with(plots):
--------------------------------------------------------------------------------
> with(plots);

  [animate, animate3d, conformal, contourplot, cylinderplot, densityplot,

      display, display3d, fieldplot, fieldplot3d, gradplot, gradplot3d,

      implicitplot, implicitplot3d, loglogplot, logplot, matrixplot, odeplot,

      pointplot, polarplot, polygonplot, polygonplot3d, polyhedraplot, replot,

      setoptions, setoptions3d, spacecurve, sparsematrixplot, sphereplot,

      surfdata, textplot, textplot3d, tubeplot]
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> ?animate
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> animate( [u*sin(t),u*cos(t),t=-Pi..Pi],u=1..8,view=[-8..8,-8..8]);
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> plot3d([u*sin(t),u*cos(t),u], t=-Pi..Pi, u=1..8);
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> ?animate3d
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> animate3d(cos(t*x)*sin(t*y),x=-Pi..Pi, y=-Pi..Pi,t=1..2);
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> piechart := proc(sectors)\
 # sectors is the number of different sectors plotted\
 local plot;\
 plot :=\
  seq( # sequence of color plots\
       plots[polygonplot]([[0,0],# first point of triangle\
                           # second point of triangle\
                           [cos(2*Pi*i/sectors),sin(2*Pi*i/sectors)],\
                           # third point of triangle\
                           [cos(2*Pi*(i+1)/sectors), sin(2*Pi*(i+1)/sectors)]\
                          ],\
                          color=COLOR(HUE,i/sectors)\
                         ), # finishes a single plot\
       i=0..(sectors-1) # range of sequence\
     );\
 plots[display]([plot]);\
end; # piechart\

Warning, `i` is implicitly declared local


piechart :=

    proc(sectors)
    local plot,i;
        plot := seq(plots[polygonplot]([[0,0],
            [cos(2*Pi*i/sectors),sin(2*Pi*i/sectors)],
            [cos(2*Pi*(i+1)/sectors),sin(2*Pi*(i+1)/sectors)]],
            color = COLOR(HUE,i/sectors)),i = 0 .. sectors-1);
        plots[display]([plot])
    end

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> piechart(10);
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> piechart(25);
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> seq(1,2,3);
Error, wrong number (or type) of parameters in function seq

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> seq(i,i=1..3);

                                     1, 2, 3
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> ?color
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> ?hue
  The argument passed to help was:   hue
  Sorry, unable to explain this topic.  See  ?index  for
  a list of topics which are available.

--------------------------------------------------------------------------------
> ?HUE
  The argument passed to help was:   HUE
  Sorry, unable to explain this topic.  See  ?index  for
  a list of topics which are available.

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> piechart(100);
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
>