GProjLambert Class Reference

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Class for Lambert Conformal Conic projection. More...

#include <src/gproj.h>

Inherits: GMapProj

Public Members


Detailed Description

A conic conformal projections where parallels are unequally spaced arcs of concentric circles, more closely spaced near the center of the map. Meridians are equally spaced radii of the same circles, thereby cutting parallels at right angles. Scale is true along two standard parallels, normally, or along just one. Used for maps of countries and regions with predominant east-west expanse. -- (J. Snyder, "Map Projections - A working manual").


NOP GProjLambert() [public]

Default constructor; must call init() before any conversion.

NOP GProjLambert(double r_maj, double r_min, double lat1, double lat2, double c_lon, double c_lat, double x_false, double y_false) [public]

construct a Lambert (CC) projection.

Parameters:
major/minor axis; lat1/lat2 first and second standard parallel; both are radians c_lon/c_lat central longitude and latitude; both are radians x_false/y_false false easting and northing. both are radians

Result init(double r_maj, double r_min, double lat1, double lat2, double c_lon, double c_lat, double x_false, double y_false) [public]

initialize for the Lambert projection. Must be called before any foward/inverse conversion can happen.

Parameters:
uses same parameter as in second constructor. longitudes/lattitudes are all radians.

Result forward(double lon, double lat, double& x, double& y) [public]

Forward conversion from (longitude,latitude) to Lambert coordinates in meters.

Parameters:
(lon, lat) MUST be radians!!!

Result inverse(double x, double y, double& lon, double& lat) [public]

Inverse conversion from Lambert coordinates to (longitude, latitude). (x,y) must be in meters; and (lon, lat) will be in radians.


Documentation generated by lqian@lqian-sun on Wed Jul 14 09:36:10 EDT 1999
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