Usage of angularSeparationRadians

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Computes the great circle angle between two celestial coordinates. using the Vincenty formula which is correct for all angles.

See also angularSeparationOfStrings, angularSeparationOfFields, angularSeparationOfPlanets, angularSeparation, and angularSeparationRadiansTuples.

Usage:

au.angularSeparationRadians(ra0, dec0, ra1, dec1, returnComponents=False)

ra,dec must be given in radians as is the output. 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 <4>: au.angularSeparationRadians(0,1,2,3)
  Out[4]: 1.222450611061632
CASA <3>: au.angularSeparationRadians(0,1,2,3,True)
  Out[3]: array([ 1.22245061, -2.        , -2.        ,  0.83229367])
-- ToddHunter - 2013-01-25

This topic: ALMA > TWikiUsers > ToddHunter > CasaExtensions > AngularSeparationRadians
Topic revision: 2013-02-28, ToddHunter
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