Calculating the azimuth

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(default values are for Baltray [point A] and Rockabill [Point B], both in Ireland)
(Remark: north and east are positive, south and west are negative)
Longitude/latitude method
Long A: [o
Lat A: [o
Long B: [o
Lat B: [o
GPS error:[m]
Map grid method
Grid:        Irish grid  UK grid 
OSLong A:    [m]
OSLat A:     [m]
OSLong B:    [m]
OSLat B:     [m]
Grid error: [m]
Sometimes the Irish map grid holds a letter: Instead of using a letter add the below numbers to it OSlong and OSlat:
Example Rockabill: O 32175, 62725  ->  332175, 262725

Distance between A and B: [m]
Geocentric angle: [o]
Azimuthl[o] +/- [o
Map azimuth: [o
Grid-true north differance: [o
To get a reliable difference, you NEED to input  LongA and Lat A!!!
Azimuthm[o] +/- [o]

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Last major content related changes: July 18, 2000