PlotFR - Plot a function on a fundamental region.

   USAGE:

   PlotFR(mesh, odf)
   PlotFR(mesh, odf 'param', 'value', ...)

   INPUT:

   mesh is a MeshStructure:
           describing the fundamental region to be plotted
   odf  is a vector of reals:, 
           it contains nodal point values of the function to be
           plotted;  the values are expected only for the 
           independent nodes of the mesh

   These arguments can be followed by a list of
   parameter/value pairs which control certain plotting 
   features.  Options are:

   'Symmetries'       string indicating symmetries of the FR
                      {'cubic'} | 'hexagonal'
   'ShowMesh'         on | {off}
                      to show mesh lines on the surface plot
   'Colormap'         ncolors x 3  (RGB)
                      to specify the figure's colormap; 
                      the default colormap is a brightened
                      version of `jet'
   'BrightenColormap' scalar between 0 and 1 (default=0)
                      factor for brightening the colormap;
                      a value of 0 does nothing, a value
                      of 1 makes everything white
   'NumberOfColors'   positive integer (default = 64)
                      number of colors to use in default colormap

   OUTPUT:  none

   NOTES:

   *  This function makes a figure containing side-by-side 
      plots of the surface of the given fundamental region and of 
      slices through it, with a common colorbar in the middle.

 PlotFRPerimeter - Plot perimeter of fundamental region.
   
   USAGE:

   perim =  PlotFRPerimeter(symtype)

   INPUT:

   symtype is a string,
           indicating the fundamental region type; possible
           values are:  'cubic'|'hexagonal'; if the symmetry
           type is not recognized, a warning is issued

   OUTPUT:

   perim is a column vector of line handles:
            it contains handles to the lines outlining each face,
            as returned by the matlab `plot3' function

   NOTES:

   * set `hold' to on

 PlotFRSlices - Plot slices of the fundamental region.
   
   USAGE:

   PlotFRSlices(mesh, odf, type)
   PlotFRSlices(mesh, odf, type, planes)

   INPUT:

   mesh is a MeshStructure,
        on the given fundamental region
   odf  is a vector,
        the odf values at the independent nodal points of `mesh'
   type is a string, (optional, default: 'cubic')
        indicating the symmetry type; possible values are
        'cubic' | 'hexagonal'; the slices to display
        are based on the type
   planes is an array of structures, (optional)
        each structure is expected to have components 'Point'
        and 'Normal' characterizing a plane;  if specified,
        this overrides the `type' input

   OUTPUT:  none

 PlotSphere - Plot a function (pole figure) on the Sphere

   USAGE:

   PlotSphere(smesh, pf)
   PlotSphere(smesh, pf, 'param', 'value', ...)

   INPUT:

   smesh is a MeshStructure,
         on the sphere (the usual one)
   pf    is a vector, 
         the nodal point values of thefunction (pole figure) to plot

   These arguments can be followed by a list of
   parameter/value pairs which control certain plotting 
   features.  Options are:

   'ShowMesh'         on|{off}
                      to show mesh lines
   'ShowQuadrants'    {on}|off
                      to show quadrant divisions on
                      the sphere
   'UpperHemisphere'  on|{off}
                      to limit quadrant divisions to 
                      only the upper hemisphere; this only
                      applies if 'ShowQuadrants' is in
                      effect
   'Colormap'         ncolors x 3  (RGB)
                      to specify the figure's colormap; 
                      the default colormap is a brightened
                      version of `jet'
   'ShowColorBar'     on|{off}
                      to display a colorbar or not

   OUTPUT:  none

   NOTES:

   *  `hold on' is in effect following this routine

 PlotSphereQuadrants - Outline quadrants on unit sphere

   USAGE:

   PlotSphereQuadrants(ndiv)
   PlotSphereQuadrants(ndiv, upper)
   
   INPUT:

   ndiv  is a positive integer, 
         the number of points per circle
   upper is a positive integer, (optional, default=0) 
         if nonzero, only the upper half is drawn

   OUTPUT:  none

 PlotSurface - Plot a function on surface in 3d.

   USAGE:

   PlotSurface(smesh, sfun)
   PlotSurface(smesh, sfun, 'param', 'value', ...)

   INPUT:

   smesh is a MeshStructure,
         on a 2D surface in 3D
   sfun  is a vector, 
         the values on the nodes of the surface mesh

   These arguments can be followed by a list of
   parameter/value pairs which control certain plotting 
   features.  Options are:
   
   'ShowMesh'    on|{off}
                 to show the edges of the mesh

   OUTPUT:  none

   NOTES:

   *  This routine calls `trimesh' with interpolated face color.