function [lat,lon,h]=xyz2ell3(X,Y,Z,a,b,e2)% XYZ2ELL3  Converts cartesian coordinates to ellipsoidal.%   Uses direct algorithm in B.R. Bowring, "The accuracy of%   geodetic latitude and height equations", Survey%   Review, v28 #218, October 1985, pp.202-206.  Vectorized.%   See also XYZ2ELL, XYZ2ELL2.% Version: 18 Jan 96% Useage:  [lat,lon,h]=xyz2ell3(X,Y,Z,a,b,e2)% Input:   X \%          Y  > vectors of cartesian coordinates in CT system (m)%          Z /%          a   - ref. ellipsoid major semi-axis (m)%          b   - ref. ellipsoid minor semi-axis (m)%          e2  - ref. ellipsoid eccentricity squared% Output:  lat - vector of ellipsoidal latitudes (radians)%          lon - vector of ellipsoidal longitudes (radians)%          h   - vector of ellipsoidal heights (m)lon=atan2(Y,X);e=e2*(a/b)^2;p=sqrt(X.*X+Y.*Y);r=sqrt(p.*p+Z.*Z);u=atan(b.*Z.*(1+e.*b./r)./(a.*p));lat=atan((Z+e.*b.*sin(u).^3)./(p-e2.*a.*cos(u).^3));v=a./sqrt(1-e2.*sin(lat).^2);h=p.*cos(lat)+Z.*sin(lat)-a*a./v;