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Convert geodetic latitude to authalic, conformal, isometric, or rectifying latitude

Syntax

lat = forward(converter,phi)

lat = forward(converter,phi,angleUnit)

Description

lat = forward(converter,phi) returns the authalic, conformal, isometric, or rectifying latitude coordinates corresponding to geodetic latitude coordinates phi.

lat = forward(converter,phi,angleUnit) specifies the units of input phi.

Examples

Convert Geodetic Latitude to Authalic Latitude

Specify geodetic latitude coordinates and create an authalic latitude converter. Then, convert the coordinates.

 phi = [-90 -67.5 -45 -22.5 0 22.5 45 67.5 90];
 conv = map.geodesy.AuthalicLatitudeConverter(wgs84Ellipsoid);
 beta = forward(conv,phi)

beta = 1×9

  -90.0000  -67.4092  -44.8717  -22.4094         0   22.4094   44.8717   67.4092   90.0000

Convert Geodetic Latitude to Isometric Latitude

Specify geodetic latitude coordinates and create an isometric latitude converter. Then, convert the coordinates.

phi = [-90 -67.5 -45 -22.5 0 22.5 45 67.5 90];
conv = map.geodesy.IsometricLatitudeConverter(wgs84Ellipsoid);
psi = forward(conv,phi)

psi = 1×9

      -Inf   -1.6087   -0.8766   -0.4006         0    0.4006    0.8766    1.6087       Inf

Convert Geodetic Latitude to Rectifying Latitude Using Radians

Specify geodetic latitude coordinates and convert them to radians. Create a rectifying latitude converter. Then, convert the coordinates by specifying the angle unit as 'radians'.

phi = [-90 -67.5 -45 -22.5 0 22.5 45 67.5 90];
phirad = deg2rad(phi);
conv = map.geodesy.RectifyingLatitudeConverter(wgs84Ellipsoid);
mu = forward(conv,phirad,'radians')

mu = 1×9

   -1.5708   -1.1763   -0.7829   -0.3909         0    0.3909    0.7829    1.1763    1.5708

Input Arguments

converter — Latitude converter

AuthalicLatitudeConverter, ConformalLatitudeConverter, IsometricLatitudeConverter, or RectifyingLatitudeConverter object

Latitude converter, specified as an AuthalicLatitudeConverter, ConformalLatitudeConverter, IsometricLatitudeConverter, or RectifyingLatitudeConverter object.

phi — Geodetic latitude coordinates

numeric scalar, vector, matrix, or N-D array

Geodetic latitude coordinates, specified as a numeric scalar value, vector, matrix, or N-D array. If angleUnit is not supplied, phi is in degrees. Otherwise, values of phi must be consistent with the units of angleUnit.

Data Types: single | double

angleUnit — Unit of geodetic latitude coordinates

'degrees' (default) | 'radians'

Units of geodetic latitude coordinates, specified as 'degrees' or 'radians'.

Output Arguments

lat — Converted latitude coordinates

numeric scalar, vector, matrix, or N-D array

Converted latitude coordinates, returned as a numeric scalar, vector, matrix, or N-D array. lat is the same size as phi.

The interpretation of lat depends on the latitude converter. If the conversion is:

• authalic, lat represents the variable β (beta), and has the same units as phi.

• conformal, lat represents χ (chi), and has the same units as phi.

• isometric, lat represents ψ (psi). lat is a dimensionless number and does not have an angle unit.

• rectifying, lat represents μ (mu), and has the same units as phi.