/* Input file is stdin if fname==NULL */
int
read_radec(OBSERVATION obsarray[], char *fname, int *nobs)
{
FILE *fptr;
OBSERVATION *obs;
int i;
char inbuff[256];
double jd,ra,dec,elat,elon;
if (fname==NULL)
fptr = stdin;
else if ( (fptr=fopen(fname,"r"))==NULL) {
fprintf(stderr,"Error opening observations file %s\n",fname);
exit(1);
}
*nobs=0;
while ( fgets_nocomment(inbuff,255,fptr,NULL)!=NULL) {
if ( scan_observation(inbuff, &(obsarray[*nobs]))) {
fprintf(stderr,"Quitting on format error\n");
exit(1);
}
obs = &(obsarray[*nobs]);
(*nobs)++;
eq_to_ec(obs->thetax,obs->thetay,&elat,&elon,NULL);
if (*nobs==1) {
double xec, yec, zec;
/* Use first observation to set the reference frame */
jd0 = obs->obstime;
lat0 = elat;
lon0 = elon;
/* Find location of SSBARY wrt observatory at zero time */
earth_ssbary(jd0, obs->obscode, &xBary, &yBary, &zBary);
/* Negate the vector to make it earth->SSBARY*/
/* And rotate equatorial into the tangent-point coords */
xBary *= -1.; yBary *= -1.; zBary *= -1.;
xyz_eq_to_ec(xBary, yBary, zBary, &xec, &yec, &zec,NULL);
xyz_ec_to_proj(xec, yec, zec, &xBary, &yBary, &zBary, lat0, lon0, NULL);
}
/* Set time to years after jd0, rotate to tangent plane coords */
obs->obstime = (obs->obstime-jd0)*DAY;
ec_to_proj(elat,elon,&(obs->thetax),&(obs->thetay),
lat0,lon0,NULL);
/* Calculate the position of Earth at this time to avoid doing
* it many times later: */
earth3d(obs->obstime, obs->obscode,
&(obs->xe),&(obs->ye),&(obs->ze));
}
if (fname!=NULL) fclose(fptr);
return(0);
}
/* Input file is stdin if fname==NULL */
int
read_radec(OBSERVATION obsarray[], char *fname, int *nobs)
{
FILE *fptr;
OBSERVATION *obs;
int scan_status_flag;
int i;
char inbuff[256];
double jd,ra,dec,elat,elon;
if (fname==NULL)
fptr = stdin;
else if ( (fptr=fopen(fname,"r"))==NULL) {
fprintf(stderr,"Error opening observations file %s\n",fname);
exit(1);
}
*nobs=0;
while ( fgets_nocomment(inbuff,255,fptr,NULL)!=NULL) {
// obs refers to the previous observation, after the first loop.
scan_status_flag = scan_observation(inbuff, &(obsarray[*nobs]), obs);
// scanned line was 2nd line of two line format so don't advance nobs as all we did was reset the observer x/y
if (scan_status_flag == -1) {
mpc3d(obs->obstime, &(obs->xe), &(obs->ye), &(obs->ze));
continue;
}
// all other non-zero status values indicate an error.
if ( scan_status_flag == 1) {
fprintf(stderr,"Quitting on format error\n");
exit(1);
}
obs = &(obsarray[*nobs]);
(*nobs)++;
eq_to_ec(obs->thetax,obs->thetay,&elat,&elon,NULL);
if (*nobs==1) {
double xec, yec, zec;
/* Use first observation to set the reference frame */
jd0 = obs->obstime;
lat0 = elat;
lon0 = elon;
/* fprintf(stderr, "%f %f %f %d\n", elat, elon, obs->obstime, obs->obscode); */
/* Find location of SSBARY wrt observatory at zero time */
earth_ssbary(jd0, obs->obscode, &xBary, &yBary, &zBary);
/* fprintf(stderr, "%f %f %f %d\n", elat, elon, obs->obstime, obs->obscode); */
/* Negate the vector to make it earth->SSBARY*/
/* And rotate equatorial into the tangent-point coords */
xBary *= -1.; yBary *= -1.; zBary *= -1.;
xyz_eq_to_ec(xBary, yBary, zBary, &xec, &yec, &zec,NULL);
xyz_ec_to_proj(xec, yec, zec, &xBary, &yBary, &zBary, lat0, lon0, NULL);
}
/* fprintf(stderr,"%f %f", lat0, lon0); */
/* Set time to years after jd0, rotate to tangent plane coords */
obs->obstime = (obs->obstime-jd0)*DAY;
ec_to_proj(elat,elon,&(obs->thetax),&(obs->thetay),
lat0,lon0,NULL);
/* Calculate the position of Earth at this time to avoid doing
* it many times later: */
if (scan_status_flag == -2) {
mpc3d(obs->obstime, &(obs->xe), &(obs->ye), &(obs->ze));
} else {
earth3d(obs->obstime, obs->obscode,
&(obs->xe), &(obs->ye), &(obs->ze));
}
}
if (fname!=NULL) fclose(fptr);
return(0);
}
int
main(int argc, char *argv[])
{
PBASIS ptrue, pfit, ptry;
OBSERVATION futobs, obsarray[MAXOBS], *obs;
int nobs;
double tt;
ORBIT orbit;
XVBASIS xv;
double **covar, **covar_aei, **covar_xyz;
double chisq;
int dof;
char inbuff[256];
double **sigxy,a,b,PA,**derivs;
double lat,lon,**covecl;
double ra,dec, **coveq;
double xx,yy,xy,bovasqrd,det;
double now, threshold, timestart, timespan, timeend;
double besttime, bestvara, elong;
int i, refit;
if (argc!=4 || *argv[1]=='^') print_help();
/* echo the command line to output */
printf("#");
for (i=0; i<argc; i++) printf(" %s",argv[i]);
{
#include <time.h>
time_t timettt;
time(&timettt);
/* note that ctime returns string with newline at end */
printf("\n#---%s",ctime(&timettt));
}
sigxy = dmatrix(1,2,1,2);
derivs = dmatrix(1,6,1,6);
covar = dmatrix(1,6,1,6);
covar_xyz = dmatrix(1,6,1,6);
covar_aei = dmatrix(1,6,1,6);
covecl = dmatrix(1,2,1,2);
coveq = dmatrix(1,2,1,2);
if (read_abg(argv[1],&ptrue,covar)) {
fprintf(stderr, "Error input alpha/beta/gamma file %s\n",argv[1]);
exit(1);
}
if ((threshold = atof(argv[2]))<=0.) {
fprintf(stderr,"Bad observation threshold %s\n",argv[2]);
print_help();
}
if ((timespan = atof(argv[3]))<=0.) {
fprintf(stderr,"Bad time span %s\n",argv[3]);
print_help();
}
/* Read in the initial observation times */
nobs = 0;
while (fgets_nocomment(inbuff, 255, stdin, stdout)!=NULL) {
obs = &(obsarray[nobs]);
if (scan_observation(inbuff, obs)) exit(1);
/* Set time to years after jd0, don't care about coordinates here*/
obs->obstime = (obs->obstime-jd0)*DAY;
if (nobs==0) timestart = obs->obstime;
/* Calculate the position of Earth at this time to avoid doing
* it many times later: */
earth3d(obs->obstime, obs->obscode,
&(obs->xe),&(obs->ye),&(obs->ze));
/* replace with faked position */
fake_observation(&ptrue, obs);
print_radec(obs,stdout);
printf("Reobserve time %.4f opp. angle %.2f\n", obs->obstime-timestart,
opposition_angle(obs)/DTOR);
nobs++;
}
/* Get an orbit fit*/
fit_observations(obsarray, nobs, &pfit, covar, &chisq, &dof, NULL);
/*Save site and error limits to use in future */
obsarray[nobs].obscode = obsarray[nobs-1].obscode;
obsarray[nobs].dthetax = obsarray[nobs-1].dthetax;
obsarray[nobs].dthetay = obsarray[nobs-1].dthetay;
timeend = timestart + timespan;
bestvara = 1e10;
besttime = 0.;
for (now = obsarray[nobs-1].obstime; now <= timeend; ) {
/*Advance observing time */
if ( now-timestart < 2*MONTH) now+= DAY;
else now+=MONTH;
/*Get position and x uncertainty*/
/* Predict position & examine uncertainty */
obsarray[nobs].obstime = now;
obsarray[nobs].xe = -999.; /* Force evaluation of earth3d */
predict_posn(&pfit,covar,&obsarray[nobs],sigxy);
/* Compute a, b, theta of error ellipse for output */
xx = sigxy[1][1];
yy = sigxy[2][2];
xy = sigxy[1][2];
PA = 0.5 * atan2(2.*xy,(xx-yy)) * 180./PI; /*go right to degrees*/
/* Adjust for PA to be N through E, */
PA = PA-90;
if (PA<-90.) PA += 180.;
bovasqrd = (xx+yy-sqrt(pow(xx-yy,2.)+pow(2.*xy,2.)))
/ (xx+yy+sqrt(pow(xx-yy,2.)+pow(2.*xy,2.))) ;
det = xx*yy-xy*xy;
b = pow(det*bovasqrd,0.25);
a = pow(det/bovasqrd,0.25);
/* See what uncertainty in a results from this obs.*/
fit_observations(obsarray, nobs+1, &ptry, covar_aei, &chisq, &dof, NULL);
pbasis_to_bary(&ptry, &xv, derivs);
covar_map(covar_aei, derivs, covar_xyz,6,6);
orbitElements(&xv, &orbit);
aei_derivs(&xv, derivs);
covar_map(covar_xyz, derivs, covar_aei,6,6);
/* Report results of this test to output */
printf("%7.4f %.2f %.2f %.2f %9.6f %.3g %5.1f %5.1f %d\n", now-timestart,
obsarray[nobs].thetax/ARCSEC, obsarray[nobs].thetay/ARCSEC,
a/ARCSEC, sqrt(covar_aei[1][1]), sqrt(covar_aei[2][2]),
elong/DTOR, opposition_angle(&obsarray[nobs])/DTOR, nobs);
/* Go to next date if Sun is too close */
elong = elongation(&obsarray[nobs]);
if (elong < MIN_ELONG) continue;
if (a > threshold*ARCSEC) {
/* object is lost. See what prior observation was best
* for constraining a, then add it and refit orbit, continue
*/
if (besttime<=0) {
fprintf(stderr,"Object is lost before observation\n");
exit(1);
}
obsarray[nobs].obstime = besttime;
obsarray[nobs].xe = -999.;
fake_observation(&ptrue, &obsarray[nobs]);
printf("Reobserve time %.4f opp. angle %.2f\n", besttime-timestart,
opposition_angle(&obsarray[nobs])/DTOR);
print_radec(&obsarray[nobs],stdout);
nobs++;
fit_observations(obsarray, nobs, &pfit, covar, &chisq, &dof, NULL);
now = besttime;
besttime = 0.;
bestvara = 1e10;
obsarray[nobs].obscode = obsarray[nobs-1].obscode;
obsarray[nobs].dthetax = obsarray[nobs-1].dthetax;
obsarray[nobs].dthetay = obsarray[nobs-1].dthetay;
} else {
/* Is this the best observation so far? */
if (covar_aei[1][1] < bestvara) {
bestvara = covar_aei[1][1];
besttime = now;
}
}
}
/*Do a final observation*/
obsarray[nobs].obstime = besttime;
obsarray[nobs].xe = -999.;
fake_observation(&ptrue, &obsarray[nobs]);
printf("Reobserve time %.4f opp. angle %.2f\n", besttime-timestart,
opposition_angle(&obsarray[nobs])/DTOR);
print_radec(&obsarray[nobs],stdout);
nobs++;
fit_observations(obsarray, nobs, &pfit, covar_aei, &chisq, &dof, NULL);
pbasis_to_bary(&pfit, &xv, derivs);
covar_map(covar_aei, derivs, covar_xyz,6,6);
orbitElements(&xv, &orbit);
aei_derivs(&xv, derivs);
covar_map(covar_xyz, derivs, covar_aei,6,6);
printf("Final uncertainty in a: %.3g\n",
sqrt(covar_aei[1][1]));
free_dmatrix(covar,1,6,1,6);
free_dmatrix(covar_xyz,1,6,1,6);
free_dmatrix(covar_aei,1,6,1,6);
free_dmatrix(derivs,1,6,1,6);
exit(0);
}
int
main(int argc, char *argv[])
{
PBASIS p;
OBSERVATION futobs, obs;
struct date_time dt;
char inbuff[256],rastring[20],decstring[20];
double **covar,**sigxy,a,b,PA,**derivs;
double lat,lon,**covecl;
double ra,dec, **coveq;
double dx, dy, chisq, elat, elon;
double xx,yy,xy,bovasqrd,det;
int i,nfields;
int iarg=1;
if (argc>1 && *argv[1]=='^') print_help();
if (read_options(&iarg, argc, argv)) print_help();
if (argc-iarg!=1) print_help();
/* echo the command line to output */
printf("#");
for (i=0; i<argc; i++) printf(" %s",argv[i]);
{
#include <time.h>
time_t timettt;
time(&timettt);
/* note that ctime returns string with newline at end */
printf("\n#---%s",ctime(&timettt));
}
sigxy = dmatrix(1,2,1,2);
derivs = dmatrix(1,2,1,2);
covar = dmatrix(1,6,1,6);
covecl = dmatrix(1,2,1,2);
coveq = dmatrix(1,2,1,2);
if (read_abg(argv[iarg],&p,covar)) {
fprintf(stderr, "Error input alpha/beta/gamma file %s\n",argv[iarg]);
exit(1);
}
while (fgets_nocomment(inbuff, 255, stdin, stdout)!=NULL) {
if (scan_observation(inbuff, &obs)) exit(1);
/* Set time to years after jd0, rotate to tangent plane coords */
obs.obstime = (obs.obstime-jd0)*DAY;
eq_to_ec(obs.thetax,obs.thetay,&elat,&elon,NULL);
ec_to_proj(elat,elon,&(obs.thetax),&(obs.thetay),
lat0,lon0,NULL);
/* Calculate the position of Earth at this time to avoid doing
* it many times later: */
earth3d(obs.obstime, obs.obscode,
&(obs.xe),&(obs.ye),&(obs.ze));
futobs.obstime = obs.obstime;
futobs.obscode = obs.obscode;
futobs.xe = -999.;
predict_posn(&p,covar,&futobs,sigxy);
/* Errors: */
dx = obs.thetax - futobs.thetax;
dy = obs.thetay - futobs.thetay;
/* Add observational errors into the uncertainty */
sigxy[1][1] += pow(obs.dthetax,2.);
sigxy[2][2] += pow(obs.dthetay,2.);
chisq = dx*dx*sigxy[2][2] -2.*dx*dy*sigxy[1][2] + dy*dy*sigxy[1][1];
chisq /= sigxy[1][1]*sigxy[2][2] - sigxy[1][2]*sigxy[2][1];
/* Compute a, b, theta of error ellipse for output */
xx = sigxy[1][1];
yy = sigxy[2][2];
xy = sigxy[1][2];
PA = 0.5 * atan2(2.*xy,(xx-yy)) * 180./PI; /*go right to degrees*/
/* Adjust for PA to be N through E, */
PA = PA-90;
if (PA<-90.) PA += 180.;
bovasqrd = (xx+yy-sqrt(pow(xx-yy,2.)+pow(2.*xy,2.)))
/ (xx+yy+sqrt(pow(xx-yy,2.)+pow(2.*xy,2.))) ;
det = xx*yy-xy*xy;
b = pow(det*bovasqrd,0.25);
a = pow(det/bovasqrd,0.25);
printf("%7.4f %9.2f %9.2f %8.3f %8.3f %8.2f %8.2f %7.2f %.2f\n",
futobs.obstime, futobs.thetax/ARCSEC, futobs.thetay/ARCSEC,
dx/ARCSEC, dy/ARCSEC,
a/ARCSEC,b/ARCSEC,PA, chisq
);
}
exit(0);
}