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geod2geoc

Convert geodetic latitude to geocentric latitude

Description

WGS84 Ellipsoid Planet

example

geocentricLatitude = geod2geoc(geodeticLatitude,height) converts an array of geodetic latitudes, geodeticLatitude, and an array of mean sea level altitudes, height, into an array of geocentric latitudes, geocentricLatitude.

[geocentricLatitude,radii] = geod2geoc(geodeticLatitude,height) returns the radius radii from the center of the planet to the center of gravity.

Specific Ellipsoid Planet

example

geocentricLatitude = geod2geoc(geodeticLatitude,height,model) converts from geodetic to geocentric latitude for a specific ellipsoid planet.

[geocentricLatitude,radii] = geod2geoc(geodeticLatitude,height,model) returns the radius radii from the center of the planet to the center of gravity.

Custom Ellipsoid Planet

example

geocentricLatitude = geod2geoc(geodeticLatitude,height,flattening,Re) converts from geodetic to geocentric latitude for a custom ellipsoid planet defined by flattening, flattening, and the equatorial radius, equatorialRadius.

[geocentricLatitude,radii] = geod2geoc(geodeticLatitude,height,flattening,Re) returns the radius radii from the center of the planet to the center of gravity.

Examples

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Determine geocentric latitude given a geodetic latitude and altitude.

[gc,r] = geod2geoc(45,1000)
gc =
   44.8076

r =
   6.3685e+06

Determine geocentric latitude at multiple geodetic latitudes and altitudes, specifying WGS84 ellipsoid model.

[gc,r] = geod2geoc([0 45 90],[1000 0 2000],'WGS84')
gc =
         0   44.8076   90.0000

r =

   1.0e+06 *
    6.3791    6.3675    6.3588

Determine geocentric latitude at multiple geodetic latitudes, given an altitude and specifying custom ellipsoid model.

f = 1/196.877360;
Re = 3397000;
[gc,r] = geod2geoc([0 45 90],2000,f,Re)
gc =
         0   44.7084   90.0000

r =
   1.0e+06 *
    3.3990    3.3904    3.3817

Input Arguments

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Geodetic latitude, specified as an array in degrees.

Data Types: double

Mean sea-level altitude (MSL), specified as a scalar in meters.

Data Types: double

Specific ellipsoid planet model, specified as 'WGS84'.

Data Types: double

Flattening at each pole, specified as a scalar.

Data Types: double

Equatorial radius, specified as a scalar in meters.

Data Types: double

Output Arguments

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Geocentric latitudes, returned as an array in degrees. Latitude values can be any value. However, values of +90 and -90 may return unexpected values because of singularity at the poles.

Radii from the center of the planet, returned as an array in meters.

Limitations

This function generates a geocentric latitude that lies between ±90 degrees.

References

[1] Stevens, Brian L., Frank L. Lewis, Aircraft Control and Simulation, Wiley–Interscience, 1992.

Introduced in R2006b