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Prism - An extrusion of a region into higher dimensions

Description:
A Prism is a Region which represents an extrusion of an existing Region into one or more orthogonal dimensions (specified by another Region). If the Region to be extruded has N axes, and the Region defining the extrusion has M axes, then the resulting Prism will have (M$+$N) axes. A point is inside the Prism if the first N axis values correspond to a point inside the Region being extruded, and the remaining M axis values correspond to a point inside the Region defining the extrusion.

As an example, a cylinder can be represented by extruding an existing Circle, using an Interval to define the extrusion. Ih this case, the Interval would have a single axis and would specify the upper and lower limits of the cylinder along its length.

Constructor Function:
astPrism
Inheritance
The Prism class inherits from the Region class.
Attributes
The Prism class does not define any new attributes beyond those which are applicable to all Regions.
Functions
The Prism class does not define any new functions beyond those which are applicable to all Regions.


next up previous 264
Next: RateMap - Mapping which represents differentiation
Up: AST Class Descriptions
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AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 211
R.F. Warren-Smith & D.S. Berry
24th May 2011
E-mail:ussc@star.rl.ac.uk

Copyright (C) 2009 Science \& Technology Facilities Council