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Using a Plot as a Frame

Every Plot is also a Frame, so can be used to obtain the values of Frame attributes such as a Title, axis Labels, axis Units, etc., which are typically used when displaying data and/or coordinates. These attributes are, as for any FrameSet, derived from the current Frame of the Plot ([*]). They are also used automatically when using the Plot to plot coordinate axes and coordinate grids (e.g. for labelling them--[*]).

Because the current Frame of a Plot represents physical coordinates, any Frame operation applied to the Plot will effectively be working in this coordinate system. For example, the AST_DISTANCE and AST_OFFSET routines will compute distances and offsets in physical coordinate space, and AST_FORMAT will format physical coordinates in an appropriate way for display.


next up previous 264
Next: Regions of Valid Physical Coordinates
Up: Producing Graphical Output (Plots)
Previous: Using a Plot as a Mapping

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