cyberflamego / nzgd2000tonztm2000

New Zealand Map Grid routines

The files nzmg.c and nzmg.h contain ANSI C code for converting coordinates between the New Zealand Map Grid and latitude and longitude on the New Zealand Geodetic Datum 1949.

The code uses one precompiler macro.

TEST_NZMG: if defined causes nzmg.c to compile into a test program which converts NZMG coordinates to NZGD49 and back again. The file TEST.DAT contains sample data which can be entered into the test program - the output should match the file TEST.OUT.

The NZMG module provides two functions

void nzmg_geod( double n, double e, double *lt, double *ln ); void geod_nzmg( double lt, double ln, double *n, double *e );

The first converts a northing n and easting e to a latitude lt and longitude ln, and the second performs the inverse function.

Northings and eastings are in metres. Latitudes and longitudes are in radians.

Sourced from https://www.linz.govt.nz/data/geodetic-services/download-geodetic-software