rcurve

Ellipsoidal radii of curvature

Syntax

r = rcurve(ellipsoid,lat)
r = rcurve('parallel',ellipsoid,lat)
r = rcurve('meridian',ellipsoid,lat)
r = rcurve('transverse',ellipsoid,lat)
r = rcurve(..., angleunits)

Description

r = rcurve(ellipsoid,lat) and r = rcurve('parallel',ellipsoid,lat) return the parallel radius of curvature at the latitude lat for a reference ellipsoid defined by ellipsoid, which can be a referenceSphere, referenceEllipsoid, or oblateSpheroid object, or a vector of the form [semimajor_axis eccentricity]. r is in units of length consistent with those used for the semimajor axis. lat is in 'degrees'.

r = rcurve('meridian',ellipsoid,lat) returns the meridional radius of curvature, which is the radius of curvature in the plane of a meridian at the latitude lat.

r = rcurve('transverse',ellipsoid,lat) returns the transverse radius of curvature, which is the radius of a curvature in a plane normal to the surface of the ellipsoid and normal to a meridian, at the latitude lat.

r = rcurve(..., angleunits) specifies the units of the input lat. angleunits can be 'degrees' or 'radians'.

Examples

The radii of curvature of the default ellipsoid at 45º, in kilometers:

r = rcurve('transverse',referenceEllipsoid('earth','km'),...
            45,'degrees')

r =
   6.3888e+03

r = rcurve('meridian',referenceEllipsoid('earth','km'),...
            45,'degrees')

r =
   6.3674e+03

r = rcurve('parallel',referenceEllipsoid('earth','km'),...
            45,'degrees')

r =
   4.5024e+03

Version History

Introduced before R2006a

See Also