[Proj] Distance calculations

[Irwin Scollar]

Oscar van Vlijmen wrote with respect to:

Tsutomu Saito, The computation of long geodesics on the ellipsoid through
Gaussian quadrature, Bull. Geod. 53 (1979), pp. 165-177

Sadly, these papers are not on-line for free.

I have a scanned copy of Saito 1979 in PDF 
format.  If anyone wants one, just ask off-line.

Although Bessel-Helmert is the basis for most 
things we have been discussing, implementations 
differ considerably and hence questions of 
numerical accuracy and speed enter.

The Borre reference I cited in an earlier reply 
has a matlab version called bessel_1.m which can 
be downloaded from Borre's web site.or as 
http://read.pudn.com/downloads85/sourcecode/comm/326312/BESSEL_2.M__.htm

There is also a fairly short method due to 
Sjöberg:  Sjöberg LE (2006) Direct solutions to 
the direct and indirect geodetic
problems on the ellipsoid. Zeitschrift f 
Vermessungswesen 131:35–39 which may be of more than academic interest.

Irwin Scollar