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Convert from equal area to Greenwich coordinates


[lat,lon] = eqa2grn(x,y)
[lat,lon] = eqa2grn(x,y,origin)
[lat,lon] = eqa2grn(x,y,origin,ellipsoid)
[lat,lon] = eqa2grn(x,y,origin,units)
mat = eqa2grn(x,y,origin...)


[lat,lon] = eqa2grn(x,y) converts the equal-area coordinate points x and y to the Greenwich (standard geographic) coordinates lat and lon.

[lat,lon] = eqa2grn(x,y,origin) specifies the location in the Greenwich system of the x-y origin (0,0). The two-element vector origin must be of the form [latitude longitude]. The default places the origin at the Greenwich coordinates (0º,0º).

[lat,lon] = eqa2grn(x,y,origin,ellipsoid) specifies the ellipsoidal model of the figure of the Earth using ellipsoid. ellipsoid is a referenceSphere, referenceEllipsoid, or oblateSpheroid object, or a vector of the form [semimajor_axis eccentricity]. The ellipsoid is a unit sphere by default.

[lat,lon] = eqa2grn(x,y,origin,units) specifies the units for the outputs, where units is any valid angle units value. The default value is 'degrees'.

mat = eqa2grn(x,y,origin...) packs the outputs into a single variable.

This function converts data from equal-area x-y coordinates to geographic (latitude-longitude) coordinates. The opposite conversion can be performed with grn2eqa.


[lat,lon] = eqa2grn(.5,.5)

lat =
lon =

Version History

Introduced before R2006a

See Also