GProj library - Functions for reading datum parameters from the location database. More...

#include <unistd.h>
#include <ctype.h>
#include <string.h>
#include <stdlib.h>
#include <math.h>
#include <grass/gis.h>
#include <grass/glocale.h>
#include <grass/gprojects.h>
#include "local_proto.h"

Include dependency graph for ellipse.c:

Go to the source code of this file.

Functions
int	GPJ_get_ellipsoid_params (double a, double e2, double *rf)
	Get the ellipsoid parameters from the database. More...

int	GPJ__get_ellipsoid_params (const struct Key_Value proj_keys, double a, double e2, double rf)
	Get the ellipsoid parameters from proj keys structure. More...

int	GPJ_get_ellipsoid_by_name (const char name, struct gpj_ellps estruct)
	Looks up ellipsoid in ellipsoid table and returns the a, e2 parameters for the ellipsoid. More...

struct ellps_list *	read_ellipsoid_table (int fatal)

void	GPJ_free_ellps (struct gpj_ellps *estruct)
	Free ellipsoid data structure. More...

void	free_ellps_list (struct ellps_list *elist)

Detailed Description

GProj library - Functions for reading datum parameters from the location database.

Author: Paul Kelly <paul-grass stjohnspoint.co.uk>

This program is free software under the GNU General Public License (>=v2). Read the file COPYING that comes with GRASS for details.

Definition in file ellipse.c.

Function Documentation

◆ free_ellps_list()

void free_ellps_list ( struct ellps_list * elist )

Definition at line 316 of file ellipse.c.

References G_free(), and NULL.

Referenced by GPJ_get_ellipsoid_by_name().

◆ GPJ__get_ellipsoid_params()

int GPJ__get_ellipsoid_params	(	const struct Key_Value *	proj_keys,
		double *	a,
		double *	e2,
		double *	rf
	)

Get the ellipsoid parameters from proj keys structure.

If the PROJECTION_FILE exists in the PERMANENT mapset, read info from that file, otherwise return WGS 84 values.

Dies with diagnostic if there is an error.

Parameters

	proj_keys	proj definition
[out]	a	semi-major axis
[out]	e2	first eccentricity squared
[out]	rf	reciprocal of the ellipsoid flattening term

Returns: 1 on success; 0 default values used.

Definition at line 73 of file ellipse.c.

◆ GPJ_free_ellps()

void GPJ_free_ellps ( struct gpj_ellps * estruct )

Free ellipsoid data structure.

Parameters

estruct data structure to be freed

Definition at line 309 of file ellipse.c.

References G_free(), gpj_ellps::longname, and gpj_ellps::name.

◆ GPJ_get_ellipsoid_by_name()

int GPJ_get_ellipsoid_by_name	(	const char *	name,
		struct gpj_ellps *	estruct
	)

Looks up ellipsoid in ellipsoid table and returns the a, e2 parameters for the ellipsoid.

Parameters

	name	ellipsoid name
[out]	estruct	ellipsoid

Returns: 1 on success; -1 if not found in table

Definition at line 160 of file ellipse.c.

References gpj_ellps::a, gpj_ellps::es, free_ellps_list(), G_store(), G_strcasecmp(), list, gpj_ellps::longname, gpj_ellps::name, NULL, read_ellipsoid_table(), and gpj_ellps::rf.

◆ GPJ_get_ellipsoid_params()

int GPJ_get_ellipsoid_params	(	double *	a,
		double *	e2,
		double *	rf
	)

Get the ellipsoid parameters from the database.

If the PROJECTION_FILE exists in the PERMANENT mapset, read info from that file, otherwise return WGS 84 values.

Dies with diagnostic if there is an error.

Parameters

[out]	a	semi-major axis
[out]	e2	first eccentricity squared
[out]	rf	reciprocal of the ellipsoid flattening term

Returns: 1 on success; 0 default values used.

Definition at line 43 of file ellipse.c.

◆ read_ellipsoid_table()

struct ellps_list* read_ellipsoid_table ( int fatal )

Definition at line 224 of file ellipse.c.

References file, GPATH_MAX, and name.

Referenced by GPJ_get_ellipsoid_by_name().