RPosInvMag

Syntax

void RPosInvMag(int bm,int rn,int year,struct RadarSite *hdw,double frang, double rsep,double rx,double height, double *mlat,double *mlon,double *azm,int chisham,int old_aacgm);

Header

superdarn/invmag.h

Library

rpos

Description

The RPosInvMag function calculates the invariant magnetic co-ordinates of a radar range-beam cell.

The arguments bcrd and rcrd give the beam and range number of the cell.

The argument year defines the year for which the calculatation should be performed.

The argument hdw points to a structure containing the radar site and hardware information.

The distance to the first range and the range separation are given by the arguments frang, rsep.

The argument rxrise gives the receiver rise time, if this is set to zero then the receiver rise time will be taken from the hardware table.

If the argument height is less than or equal to 90 it corresponds to the elevation angle in degrees associated with the calculation, otherwise is corresponds to the height in kilometers.

The invariant magnetic latitude, longitude and azimuth are stored stored at the locations pointed to by the arguments mlat, mlon, and azm.

If the argument chisham is set to (1) then the Chisham et al. [2008] virtual height model is used instead of the standard model.

If the argument old_aacgm is set to (1) then the old AACGM coefficients are used instead of the v2 coefficients [Shepherd, 2014].

Returns

None

Errors

None

Example

Source Code: RPosInvMag.c

/* RPosInvMag
   ==========
   Author: R.J.Barnes

Copyright (c) 2012 The Johns Hopkins University/Applied Physics Laboratory

This file is part of the Radar Software Toolkit (RST).

RST is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>.

Modifications:


*/


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

#include "rtypes.h"
#include "radar.h"
#include "invmag.h"

struct RadarNetwork *network; 
struct RadarSite *site; 

int main(int argc,char *argv[]) {
  char *envstr;
  FILE *fp;
  char *code=NULL;
  int st;
  int bm,rng;
  int frang=180,rsep=45,rxrise=100.0;
  double hgt=150.0;
  double lat,lon,azm;

  envstr=getenv("SD_RADAR");
  if (envstr==NULL) {
    fprintf(stderr,"Environment variable 'SD_RADAR' must be defined.'n");
    exit(-1);
  }

  fp=fopen(envstr,"r");

  if (fp==NULL) {
    fprintf(stderr,"Could not locate radar information file.'n");
    exit(-1);
  }

  network=RadarLoad(fp);
  fclose(fp); 
  if (network==NULL) {
    fprintf(stderr,"Failed to read radar information.'n");
    exit(-1);
  }

  envstr=getenv("SD_HDWPATH");
  if (envstr==NULL) {
    fprintf(stderr,"Environment variable 'SD_HDWPATH' must be defined.'n");
    exit(-1);
  }

  RadarLoadHardware(envstr,network);
  
  code=argv[1];
  bm=atoi(argv[2]);
  rng=atoi(argv[3]);

  st=RadarGetID(network,code);

  site=RadarYMDHMSGetSite(RadarGetRadar(network,st),2002,8,30,10,30,0);

  RPosInvMag(bm,rng,2002,site,frang,rsep,rxrise,hgt,&lat,&lon,&azm);

  fprintf(stdout,"RPosInvMag'n");
  fprintf(stdout,"%s bm=%d rng=%d'n",code,bm,rng);
  fprintf(stdout,"lat=%g lon=%g azm=%g'n",lat,lon,azm);



  return 0;
}