plotNormals Plot normal vectors of point cloud in 3d.
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  DESCRIPTION/NOTES
  * Only the normals of active points are visualized.
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  INPUT
  1 ['Arrows', arrows]
    Logical value defining if normals are visualized as arrows (true) or as
    simple lines (false). The visualisation of arrows is faster than the one
    with lines.
 
  2 ['Scale', scale]
    Scaling factor of normals.
 
  3 ['Color', color]
    Color of the normals. For possible values, look for 'ColorSpec' in the
    documentation.
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  EXAMPLES
  1 Plot normals scaled by factor of 10.
    pc = pointCloud('Lion.xyz', 'Attributes', {'nx' 'ny' 'nz'});
    pc.select('UniformSampling', 2);
    pc.plot('Color', 'r', 'MarkerSize', 5);
    pc.plotNormals('Color', 'y', 'Scale', 10);
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  philipp.glira@gmail.com
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