Usage of angularSeparation
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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. It also works for the az,el coordinate system.
Usage:
au.angularSeparation(ra0, dec0, ra1, dec1, returnComponents=False)
ra,dec must be given in degrees, as is the output.
If returnComponents is True, it also
returns the separation along the two coordinate system components via the following list:
[separation, separationRA, separationDec, separationRA*cosine(Dec)]
See also
angularSeparationOfStrings,
angularSeparationOfFields,
angularSeparationOfPlanets,
angularSeparationRadians, and
angularSeparationRadiansTuples.
Example
CASA <87>: au.angularSeparation(1.11252954444*15, -40.5722087725, 1.11252972222*15, -40.5722111111)
Out[87]: 3.0938755606396763e-06
CASA <88>: au.angularSeparation(1.11252954444*15, -40.5722087725, 1.11252972222*15, -40.5722111111,True)
Out[88]:
(3.0938755606396763e-06,
-2.6666999988218884e-06,
2.3386000082137881e-06,
-2.02559028330491e-06)
--
ToddHunter - 2012-09-05