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
Topic revision: r2 - 2013-02-28, ToddHunter
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