PROJ is a collection of three programs and a library for performing
cartographic projections. The programs are designed as a standard UNIX
filters to be used with other programs in the generation of maps and
charts, and as map digitizing applications. `proj' performs forward
and inverse transformation of cartographic data to or from Cartesian
coordinates with a wide range of available projection mapping
functions; `geod' performs geodesic computations for determining the
latitude, longitude and back azimuth of a terminus point given an
initial point latitude, longitude, azimuth and distance (direct) or
the forward and back azimuths and the distance between the initial and
terminus point latitudes and longitudes (inverse); `nad2nad' is a
North American Datum conversion filter to convert between the Datum of
1927 (NAD27) and that of 1983 (and which can also process State Plane
Coordinate System (SPCS) and Universal Transverse Mercator (UTM) grid
data as well as geographic data for both input and output).