angularSeparationOfTwoFields

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Computes the angular separation (in degrees) between 2 specified fields in a measurement set, using msmd.phasecenter and the Vincenty formula. See also angularSeparationOfFields and angularSeparationOfFieldsFromSource.

Usage:

angularSeparationOfTwoFields(vis, field1, field2, usemsmd='')
Inputs:
  • field1, field2: the field IDs (integers)
  • usemsmd: if specified, then use this existing instance of msmd rather than creating a new one

Example:

CASA <2>: au.angularSeparationOfTwoFields('uid___A002_Xac5575_X43ef.ms.split.cal',1,2)
{'type': 'direction', 'm1': {'value': -0.5020182545147964, 'unit': 'rad'}, 'm0': {'value': -0.9342156255641537, 'unit': 'rad'}, 'refer': 'ICRS'} {'type': 'direction', 'm1': {'value': -0.5740965419866287, 'unit': 'rad'}, 'm0': {'value': -0.939890563627013, 'unit': 'rad'}, 'refer': 'ICRS'}                                                                                                                        
  Out[2]: 4.1392008825455067    
-- ToddHunter - 2016-01-20

This topic: ALMA > TWikiUsers > ToddHunter > CasaExtensions > AngularSeparationOfTwoFields
Topic revision: 2016-04-04, ToddHunter
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