GProjAlbers Class Reference

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Albers Conical equal-area projection class. More...

#include <src/gproj.h>

Inherits: GMapProj

Public Members


Detailed Description

One of the most commonly used projection for maps of theconterminous United States. It uses two standard parallels.


NOP GProjAlbers() [public]

this constructor has no parameters. You mush call init() before any projection can take place using this object.

NOP GProjAlbers(double r_maj, double r_min, double lat1, double lat2, double lon0, double lat0, double fs_east=0, double fs_north=0) [public]

create an Albers map projection object with the given parameters.

Parameters:
r_maj, r_min is the major/minor axis of the earth lat1/lat2 is the first and second standard parallel (in radians) lon0/lat0 is the central longitude and origin latitude (in radians) fs_east/fs_north is the false easting/norhting.

Result init(double r_maj, double r_min, double lat1, double lat2, double lon0, double lat0, double fs_east=0, double fs_north=0) [public]

setup the parameters for the Albers projection. This is called by the constructor with the same set of parameters.

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

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

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

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

Inverse conversion from Albers 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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