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 A Library for Handling
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Description: 
This function returns a pointer to a new 
Polygon that contains a subset
of the vertices in the supplied Polygon. The subset is chosen so that the
returned Polygon is a good approximation to the supplied Polygon, within the
limits specified by the supplied parameter values. That is, the density of
points in the returned Polygon is greater at points where the curvature of
                                                                                       
                                                                                       
the boundary of the supplied Polygon is greater.  
Synopsis 
 AstPolygon
astDownsize(
AstPolygon this,
double maxerr, int maxvert )  
 Parameters: 
  this  
 Pointer to the Polygon.  
  maxerr  
The maximum allowed discrepancy between the supplied and returned Polygons, expressed
as a geodesic distance within the Polygon’ s coordinate frame. If this is zero or less,
the returned Polygon will have the number of vertices specified by maxvert.  
 
maxvert  
 The maximum allowed number of vertices in the returned Polygon. If
this is less than 3, the number of vertices in the returned Polygon will be
the minimum needed to achieve the maximum discrepancy specified by maxerr.
    Returned Value 
  astDownsize()  
 Pointer to the new Polygon.  
    Notes: 
 Copyright (C) 2021 East Asian Observatory
  -  ←Prev 
- AST
 A Library for Handling
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Coordinate Systems
 in Astronomy
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