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TimeMap - Sequence of time coordinate conversions

Description:
A TimeMap is a specialised form of 1-dimensional Mapping which can be used to represent a sequence of conversions between standard time coordinate systems.

When a TimeMap is first created, it simply performs a unit (null) Mapping. Using the AST_TIMEADD routine, a series of coordinate conversion steps may then be added. This allows multi-step conversions between a variety of time coordinate systems to be assembled out of a set of building blocks.

For details of the individual coordinate conversions available, see the description of the AST_TIMEADD routine.

Constructor Function:
AST_TIMEMAP (also see AST_TIMEADD)
Inheritance
The TimeMap class inherits from the Mapping class.
Attributes
The TimeMap class does not define any new attributes beyond those which are applicable to all Mappings.
Functions
In addition to those routines applicable to all Mappings, the following routine may also be applied to all TimeMaps:

  • AST_TIMEADD: Add a time coordinate conversion to an TimeMap


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Next: TranMap - Mapping with specified forward and inverse transformations
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AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 210
R.F. Warren-Smith & D.S. Berry
24th May 2011
E-mail:ussc@star.rl.ac.uk

Copyright (C) 2009 Science \& Technology Facilities Council