Usage of angularSeparationRadiansTuples
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Computes the great circle angle between two celestial coordinates.
using the
Vincenty formula which is correct for all
angles, as long as you use atan2() to handle a zero denominator.
See also
angularSeparationOfStrings,
angularSeparationOfFields,
angularSeparationOfPlanets,
angularSeparationRadians, and
angularSeparation.
Usage:
au.angularSeparationRadiansTuples([ra0, dec0], [ra1, dec1], returnComponents=False)
- ra,dec must be given in tuples with units of radians.
- The output is also given in radians.
- It also works for the az,el coordinate system.
- If returnComponents is True, it also returns the separation along the two coordinate system components via the following array: [separation, separationRA, separationDec, separationRA*cosine(Dec)] .
Examples:
CASA <6>: au.angularSeparationRadiansTuples([0,0],[1,1])
Out[6]: 1.2745557823062941
CASA <7>: au.angularSeparationRadiansTuples([0,0],[1,1],True)
Out[7]: array([ 1.27455578, -1. , -1. , -0.87758256])
--
ToddHunter - 2013-01-25