AACGMConvert

Syntax

int AACGMConvert(double ilat,double ilon,double hgt,double *olat,double *olon,double *r,int flg);

Header

analysis/aacgm.h

Library

aacgm

Description

The AACGMConvert function converts to and from Altitude Adjusted Corrected Geo-Magnetic Coordinates.

The arguments ilat, ilon, and hgt give the input latitude and longitude in degrees, and height of the conversion in kilometers. The latitude and longitude after the conversion are stored at the locations pointed to by the arguments olat and olon. The accuracy of the transformation is measured in terms of how close the conversion came to the unit circle, and ideal conversion being (1.0). This value is stored at the location pointed to by the argument r. The argument flg indicates what kind of transformation should be performed, a value of (0) will convert from geographic to geomagnetic coordinates, and a value of (1) will convert back from geomagnetic to geographic coordinates.

Returns

Returns zero on success. On error, a (-1) is returned.

Errors

On error, a (-1) is returned.

Example

Source Code: AACGMConvert.c

/* AACGMConvert.c
   ==============
   Author: R.J.Barnes
*/


#include <stdio.h>
#include <stdlib.h>
#include "aacgm.h"


int main(int argc,char *argv[]) {

  double ilat,ilon,hgt;
  double olat,olon,r;
  int flg;
  int s;

  ilat=85.0;
  ilon=45.0;
  hgt=150.0;

  flg=0;
  
  s=AACGMConvert(ilat,ilon,hgt,&olat,&olon,&r,flg);
  if (s !=0) {
    fprintf(stderr,"Error in AACGM conversion.'n");
    exit(-1);
  }
  fprintf(stdout,"AACGMConvert'n");
  fprintf(stdout,"Input: lat=%g, lon=%g, height=%g'n",ilat,ilon,hgt);
  fprintf(stdout,"Output: lat=%g, lon=%g'n",olat,olon);
  return 0;
}