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track2

Geographic track points from starting and ending points

    Description

    Track Points Along Unit Sphere

    example

    [lattrk,lontrk] = track2(lat1,lon1,lat2,lon2) finds the latitude and longitude coordinates of points along a great circle track from the starting point with coordinates lat1 and lon1 to the ending point with coordinates lat2 and lon2. This syntax references the coordinates to a unit sphere and assumes that all input arguments are in degrees.

    [lattrk,lontrk] = track2(lat1,lon1,lat2,lon2,units) specifies the angle units units for the inputs and outputs.

    Track Points Along Ellipsoid

    example

    [lattrk,lontrk] = track2(lat1,lon1,lat2,lon2,ellipsoid) finds track points along a geodesic on the reference ellipsoid ellipsoid.

    [lattrk,lontrk] = track2(lat1,lon1,lat2,lon2,ellipsoid,units) specifies both the reference ellipsoid and the units for the coordinates.

    [lattrk,lontrk] = track2(lat1,lon1,lat2,lon2,ellipsoid,units,npts) specifies the number of track points to find.

    Additional Options

    example

    [lattrk,lontrk] = track2(method,___), where method is "rh", calculates track points along rhumb lines. The default for method is "gc", which calculates track points along great circles (for spheres) or geodesics (for ellipsoids).

    mat = track2(___) returns the latitude and longitude coordinates of the track points in the matrix mat.

    Examples

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    Find points along a great circle track from New York City to Paris.

    [latgc,longc] = track2(40.71,-74.01,48.86,2.35);

    Find points along a rhumb line track between the same cities.

    [latrh,lonrh] = track2("rh",40.71,-74.01,48.86,2.35);

    Compare the great circle and rhumb line tracks by displaying the track points on a map. Use a blue line for the great circle track and a red line for the rhumb line track.

    geoplot(latgc,longc,"b")
    hold on
    geoplot(latrh,lonrh,"r")

    Create a World Geodetic System of 1984 (WGS84) reference ellipsoid with a length unit of nautical miles.

    wgs84 = wgs84Ellipsoid("nm");

    Find points along a geodesic track from New York City to Paris.

    [lattrk,lontrk] = track2(40.71,-74.01,48.86,2.35,wgs84);

    Display the track on a map.

    geoplot(lattrk,lontrk)

    Figure contains an axes object. The axes object contains an object of type line.

    Input Arguments

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    Latitude of the starting point, specified as a scalar or column vector.

    The sizes of lat1 and lon1 must match.

    To find multiple tracks from a single starting point, specify lat1 and lon1 as scalars and lat2 and lon2 as column vectors.

    Data Types: single | double

    Longitude of the starting point, specified as a scalar or column vector.

    The sizes of lat1 and lon1 must match.

    To find multiple tracks from a single starting point, specify lat1 and lon1 as scalars and lat2 and lon2 as column vectors.

    Data Types: single | double

    Latitude of the ending point, specified as a scalar or column vector.

    The sizes of lat2 and lon2 must match.

    To find multiple tracks from a single starting point, specify lat1 and lon1 as scalars and lat2 and lon2 as column vectors.

    Data Types: single | double

    Longitude of the ending point, specified as a scalar or column vector.

    The sizes of lat2 and lon2 must match.

    To find multiple tracks from a single starting point, specify lat1 and lon1 as scalars and lat2 and lon2 as column vectors.

    Data Types: single | double

    Angle unit, specified as one of these options:

    • "degrees" — Degrees

    • "radians" — Radians

    Data Types: char | string

    Reference ellipsoid, specified as a referenceSphere object, a referenceEllipsoid object, an oblateSpheroid object, or a two-element vector of the form [semimajor_axis eccentricity], where semimajor_axis is the length of the semimajor axis and eccentricity is the eccentricity. The values semimajor_axis and eccentricity must be of data type double.

    The default value of [1 0] represents the unit sphere.

    Track method, specified as one of these options:

    • "gc" — Find track points along a great circle path (for spheres) or a geodesic path (for ellipsoids).

    • "rh" — Find track points along a rhumb line path.

    Data Types: char | string

    Number of track points to include in lattrk and lontrk, specified as a positive integer.

    Data Types: double

    Output Arguments

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    Latitude coordinates of the track points, returned as a column vector with npts elements or a matrix of size npts-by-length(lat2). The function returns lattrk as a column vector if lat2 and lon2 are scalars, and as a matrix if lat2 and lon2 are column vectors.

    Longitude coordinates of the track points, returned as a column vector with npts elements or a matrix of size npts-by-length(lon2). The function returns lattrk as a column vector if lat2 and lon2 are scalars, and as a matrix if lat2 and lon2 are column vectors.

    Latitude and longitude coordinates of the track points, returned as a matrix equivalent to [lattrk lontrk].

    Version History

    Introduced before R2006a

    See Also

    Functions