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NatLat - Native latitude of the reference point of a FITS-WCS projection

Description:
This attribute gives the latitude of the reference point of the FITS-WCS projection implemented by a WcsMap. The value is in radians in the "native spherical" coordinate system. In some cases, this latitude value may be determined by one or more projection parameter values supplied for the WcsMap using its PVj_m attribute.

Type:
Floating point, read-only.

Class Applicability:
WcsMap
All WcsMaps have this attribute.

Notes:
  • A value of AST__BAD is returned if no latitude value is available.
  • For a definition of the reference point for a projection, see the FITS-WCS paper.



next up previous
Next: Naxes - Number of Frame axes
Up: AST Attribute Descriptions
Previous: MinTickLen(axis) - Length of minor tick marks for a Plot

AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 210
R.F. Warren-Smith & D.S. Berry
30th April 2003
E-mail:ussc@star.rl.ac.uk

Copyright (C) 2003 Central Laboratory of the Research Councils