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Point at specified azimuth, range on sphere or ellipsoid

`[latout,lonout] = reckon(lat,lon,arclen,az)[latout,lonout] = reckon(lat,lon,arclen,az,units)[latout,lonout] = reckon(lat,lon,arclen,az,ellipsoid)[latout,lonout] = reckon(lat,lon,arclen,az,ellipsoid,units)[latout,lonout] = reckon(track,...)`

`[latout,lonout] = reckon(lat,lon,arclen,az)`,
for scalar inputs, calculates a position (`latout,lonout`)
at a given range, `arclen`, and azimuth, `az`,
along a great circle from a starting point defined by `lat` and `lon`. `lat` and `lon` are
in degrees. `arclen` must be expressed as degrees
of arc on a sphere, and equals the length of a great circle arc connecting
the point (`lat`, `lon`) to the
point (`latout`, `lonout`). `az`,
also in degrees, is measured clockwise from north. `reckon` calculates
multiple positions when given four arrays of matching size. When given
a combination of scalar and array inputs, the scalar inputs are automatically
expanded to match the size of the arrays.

`[latout,lonout] = reckon(lat,lon,arclen,az,units)`,
where

`[latout,lonout] = reckon(lat,lon,arclen,az,ellipsoid)` calculates
positions along a geodesic on an ellipsoid, as specified by `ellipsoid`. `ellipsoid` is
a `referenceSphere`, `referenceEllipsoid`, or `oblateSpheroid` object, or a vector
of the form `[semimajor_axis eccentricity]`. The
range, `arclen`, must be expressed same unit of length
as the semimajor axis of the `ellipsoid`.

`[latout,lonout] = reckon(lat,lon,arclen,az,ellipsoid,units)` calculates
positions on the specified ellipsoid with

`[latout,lonout] = reckon(track,...)` calculates
positions on great circles (or geodesics) if

Find the coordinates of the point 600 nautical miles northwest of London, UK (51.5ºN,0º) in a great circle sense:

% Convert nm distance to degrees. dist = nm2deg(600) dist = 9.9933 % Northwest is 315 degrees. pt1 = reckon(51.5,0,dist,315) pt1 = 57.8999 -13.3507

Now, determine where a plane from London traveling on a constant northwesterly course for 600 nautical miles would end up:

pt2 = reckon('rh',51.5,0,dist,315) pt2 = 58.5663 -12.3699

How far apart are the points above (distance in great circle sense)?

separation = distance('gc',pt1,pt2) separation = 0.8430 % Convert answer to nautical miles. nmsep = deg2nm(separation) nmsep = 50.6156

Over 50 nautical miles separate the two points.

`azimuth` | `distance` | `dreckon` | `km2deg` | `track` | `track1` | `track2`

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