*  Index   : The index of a given datum in the datum table           (input)
 *  Code    : The ellisoid code for the ellipsoid associated with the (output)
 *               datum referenced by index 
 */


  long Retrieve_Datum_Type ( const long Index,
                             Datum_Type *Type );
/*
 *  The function Retrieve_Datum_Type returns the type of the datum referenced by
 *  index.
 *
 *  Index   : The index of a given datum in the datum table         (input)
 *  Type    : The type of the datum referenced by index             (output)
 */


  long Datum_Seven_Parameters ( const long Index, 
                                double *Delta_X,
                                double *Delta_Y,
                                double *Delta_Z,
                                double *Rx,
                                double *Ry,
                                double *Rz,
                                double *Scale_Factor );
/*
 *   The function Datum_Seven_Parameters returns the seven parameters
 *   for the datum referenced by index.
 *
 *    Index      : The index of a given datum in the datum table   (input)
 *    Delta_X    : X translation in meters                         (output)
 *    Delta_Y    : Y translation in meters                         (output)
 *    Delta_Z    : Z translation in meters                         (output)
 *    Rx         : X rotation in radians                           (output)
 *    Rx         : Y rotation in radians                           (output)
 *    Ry         : Z rotation in radians                           (output)
 *    Scale_Factor : Scale factor                                  (output)
 */


  long Datum_Three_Parameters ( const long Index, 
                                double *Delta_X,
                                double *Delta_Y,
                                double *Delta_Z);
/*
 *   The function Datum_Three_Parameters returns the three parameters 
 *   for the datum referenced by index.
 *
 *    Index      : The index of a given datum in the datum table   (input)
 *    Delta_X    : X translation in meters                         (output)
 *    Delta_Y    : Y translation in meters                         (output)
 *    Delta_Z    : Z translation in meters                         (output)
 */


  long Datum_Errors ( const long Index,
                      double *Sigma_X,
                      double *Sigma_Y,
                      double *Sigma_Z);
/*
 *   The function Datum_Errors returns the standard errors in X,Y, & Z 
 *   for the datum referenced by index.
 *
 *    Index      : The index of a given datum in the datum table   (input)
 *    Sigma_X    : Standard error in X in meters                   (output)
 *    Sigma_Y    : Standard error in Y in meters                   (output)
 *    Sigma_Z    : Standard error in Z in meters                   (output)
 */


  long Datum_Valid_Rectangle ( const long Index,
                               double *South_latitude,
                               double *North_latitude,
                               double *West_longitude,
                               double *East_longitude);
/*
 *   The function Datum_Valid_Rectangle returns the edges of the validity 
 *   rectangle for the datum referenced by index.
 *
 *   Index          : The index of a given datum in the datum table   (input)
 *   South_latitude : Southern edge of validity rectangle in radians  (input)
 *   North_latitude : Northern edge of validity rectangle in radians  (input)
 *   West_longitude : Western edge of validity rectangle in radians   (input)
 *   East_longitude : Eastern edge of validity rectangle in radians   (input)
 */


  long Datum_User_Defined ( const long Index,
	                          long *result );

/*
 *    Index    : Index of a given datum in the datum table (input)
 *    result   : Indicates whether specified datum is user defined (1)
 *               or not (0)                                (output)
 *
 *  The function Get_Datum_User_Defined checks whether or not the specified datum is 
 *  user defined. It returns 1 if the datum is user defined, and returns
 *  0 otherwise. If index is valid DATUM_NO_ERROR is returned, otherwise
 *  DATUM_INVALID_INDEX_ERROR is returned.
 */


  long Valid_Datum ( const long Index,
                     double latitude,
                     double longitude,
                     long *result );
/*
 *  This function checks whether or not the specified location is within the 
 *  validity rectangle for the specified datum.  It returns zero if the specified
 *  location is NOT within the validity rectangle, and returns 1 otherwise.
 *
 *   Index     : The index of a given datum in the datum table      (input)
 *   latitude  : Latitude of the location to be checked in radians  (input)
 *   longitude : Longitude of the location to be checked in radians (input)
 *   result    : Indicates whether location is inside (1) or outside (0)
 *               of the validity rectangle of the specified datum   (output)
 */


  long Geocentric_Shift_To_WGS84 (const long Index,
                                  const double X,
                                  const double Y,
                                  const double Z,
                                  double *X_WGS84,
                                  double *Y_WGS84,
                                  double *Z_WGS84);
/*
 *  This function shifts a geocentric coordinate (X, Y, Z in meters) relative
 *  to the datum referenced by index to a geocentric coordinate (X, Y, Z in
 *  meters) relative to WGS84.
 *
 *  Index   : Index of local datum                       (input)
 *  X       : X coordinate relative to the source datum  (input)
 *  Y       : Y coordinate relative to the source datum  (input)
 *  Z       : Z coordinate relative to the source datum  (input)
 *  X_WGS84 : X coordinate relative to WGS84             (output)
 *  Y_WGS84 : Y coordinate relative to WGS84             (output)
 *  Z_WGS84 : Z coordinate relative to WGS84             (output)
 */


  long Geocentric_Shift_From_WGS84 (const double X_WGS84,
                                    const double Y_WGS84,
                                    const double Z_WGS84,
                                    const long Index,
                                    double *X,
                                    double *Y,
                                    double *Z);
/*
 *  This function shifts a geocentric coordinate (X, Y, Z in meters) relative
 *  to WGS84 to a geocentric coordinate (X, Y, Z in meters) relative to the
 *  local datum referenced by index.
 *
 *  X_WGS84 : X coordinate relative to WGS84                 (input)
 *  Y_WGS84 : Y coordinate relative to WGS84                 (input)
 *  Z_WGS84 : Z coordinate relative to WGS84                 (input)
 *  Index   : Index of destination datum                     (input)
 *  X       : X coordinate relative to the destination datum (output)
 *  Y       : Y coordinate relative to the destination datum (output)
 *  Z       : Z coordinate relative to the destination datum (output)
 */


  long Geocentric_Datum_Shift ( const long Index_in,
                                const double X_in,
                                const double Y_in,
                                const double Z_in,
                                const long Index_out,
                                double *X_out,
                                double *Y_out,
                                double *Z_out);
/*
 *  This function shifts a geocentric coordinate (X, Y, Z in meters) relative
 *  to the source datum to geocentric coordinate (X, Y, Z in meters) relative
 *  to the destination datum.
 *
 *  Index_in  : Index of source datum                      (input)
 *  X_in      : X coordinate relative to source datum      (input)
 *  Y_in      : Y coordinate relative to source datum      (input)
 *  Z_in      : Z coordinate relative to source datum      (input)
 *  Index_out : Index of destination datum                 (input)
 *  X_out     : X coordinate relative to destination datum (output)
 *  Y_out     : Y coordinate relative to destination datum (output)
 *  Z_out     : Z coordinate relative to destination datum (output)
 */


  long Geodetic_Shift_To_WGS84 (const long Index,
                                const double Lat_in,
                                const double Lon_in,
                                const double Hgt_in,
                                double *WGS84_Lat,
                                double *WGS84_Lon,
                                double *WGS84_Hgt);
/*
 *  This function shifts geodetic coordinates relative to a given source datum
 *  to geodetic coordinates relative to WGS84.
 *
 *  Index     : Index of source datum                                 (input)
 *  Lat_in    : Latitude in radians relative to source datum          (input)
 *  Lon_in    : Longitude in radians relative to source datum         (input)
 *  Hgt_in    : Height in meters relative to source datum's ellipsoid (input)
 *  WGS84_Lat : Latitude in radians relative to WGS84                 (output)
 *  WGS84_Lon : Longitude in radians relative to WGS84                (output)
 *  WGS84_Hgt : Height in meters relative to WGS84 ellipsoid          (output)
 */


  long Geodetic_Shift_From_WGS84( const double WGS84_Lat,
                                  const double WGS84_Lon,
                                  const double WGS84_Hgt,
                                  const long Index,
                                  double *Lat_out,
                                  double *Lon_out,
                                  double *Hgt_out);
/*
 *  This function shifts geodetic coordinates relative to a WGS84 
 *  to geodetic coordinates relative to a given local datum.
 *                                                                   
 *  WGS84_Lat : Latitude in radians relative to WGS84                      (input)
 *  WGS84_Lon : Longitude in radians relative to WGS84                     (input)
 *  WGS84_Hgt : Height in meters relative to WGS84 ellipsoid               (input)
 *  Index     : Index of destination datum                                 (input)
 *  Lat_in    : Latitude in radians relative to destination datum          (output)
 *  Lon_in    : Longitude in radians relative to destination datum         (output)
 *  Hgt_in    : Height in meters relative to destination datum's ellipsoid (output)
 */


  long Geodetic_Datum_Shift ( const long Index_in,
                              const double Lat_in,
                              const double Lon_in,
                              const double Hgt_in,
                              const long Index_out,
                              double *Lat_out,
                              double *Lon_out,
                              double *Hgt_out);
/*
 *  This function shifts geodetic coordinates (latitude, longitude in radians
 *  and height in meters) relative to the source datum to geodetic coordinates
 *  (latitude, longitude in radians and height in meters) relative to the
 *  destination datum.
 *
 *  Index_in  : Index of source datum                                      (input)
 *  Lat_in    : Latitude in radians relative to source datum               (input)
 *  Lon_in    : Longitude in radians relative to source datum              (input)
 *  Hgt_in    : Height in meters relative to source datum's ellipsoid      (input)
 *  Index_out : Index of destination datum                                 (input)
 *  Lat_out   : Latitude in radians relative to destination datum          (output)
 *  Lon_out   : Longitude in radians relative to destination datum         (output)
 *  Hgt_out   : Height in meters relative to destination datum's ellipsoid (output)
 */


  long Datum_Shift_Error (const long Index_in,
                          const long Index_out,
                          double latitude,
                          double longitude,
                          double *ce90,
                          double *le90,
                          double *se90);
/*
 *  This function returns the 90% horizontal (circular), vertical (linear), and 
 *  spherical errors for a shift from the specified source datum to the 
 *  specified destination datum at the specified location.
 *
 *  Index_in  : Index of source datum                                      (input)
 *  Index_out : Index of destination datum                                 (input)
 *  latitude  : Latitude of point being converted in radians               (input)
 *  longitude : Longitude of point being converted in radians              (input)
 *  ce90      : Combined 90% circular horizontal error in meters           (output)
 *  le90      : Combined 90% linear vertical error in meters               (output)
 *  se90      : Combined 90% spherical error in meters                     (output)
 */


#ifdef __cplusplus 
}
#endif

#endif /* DATUM_H */