// nfd2mjd
double nfd2mjd(char *date)
{
int year,month,day,hour,min,sec;
double mjd,dday;
sscanf(date,"%04d-%02d-%02dT%02d:%02d:%02d",&year,&month,&day,&hour,&min,&sec);
dday=day+hour/24.0+min/1440.0+sec/86400.0;
mjd=date2mjd(year,month,dday);
return mjd;
}
double decode_filename(char *filename,int *satno)
{
int year,month,day,hour,min,sec;
int status;
double mjd;
status=sscanf(filename,"%6d_%4d%2d%2d_%2d%2d%2d",satno,&year,&month,&day,&hour,&min,&sec);
mjd=date2mjd(year,month,(double) day+hour/24.0+min/1440.0+sec/86400.0);
return mjd;
}
// DOY to MJD
double doy2mjd(int year,double doy)
{
int month,k=2;
double day;
if (year%4==0 && year%400!=0)
k=1;
month=floor(9.0*(k+doy)/275.0+0.98);
if (doy<32)
month=1;
day=doy-floor(275.0*month/9.0)+k*floor((month+9.0)/12.0)+30.0;
return date2mjd(year,month,day);
}
int mpc_convert (char *line, struct source *src) {
int len;
char *p;
int yr, mn, di;
double df, epoch;
double ma, aq, ecc, perih, anode, incl, nn;
len = strlen(line);
/* We need to figure out if this is a minor planet or comet entry.
Column 22 should be part of the (packed) epoch, which is always
present, for a minor planet, but blank for a comet. Numbering is
from 1, so we test array index 21, after making sure there are
enough characters. */
if(len < 22)
goto error;
if(isspace((unsigned char) line[21])) { /* comet */
/* Epoch */
if(extractint(line, len, 15, 18, &yr))
goto error;
if(extractint(line, len, 20, 21, &mn))
goto error;
if(extractintfrac(line, len, 23, 29, &di, &df))
goto error;
epoch = date2mjd(yr, mn, di) + df; /* convert to MJD(TT) */
/* Elements */
if(extractdouble(line, len, 31, 39, &aq)) /* perihelion distance, AU */
goto error;
if(extractdouble(line, len, 42, 49, &ecc)) /* eccentricity */
goto error;
if(extractdouble(line, len, 52, 59, &perih)) /* argument of perihelion, deg */
goto error;
if(extractdouble(line, len, 62, 69, &anode)) /* longitude of ascending node, deg */
goto error;
if(extractdouble(line, len, 72, 79, &incl)) /* inclination, deg */
goto error;
/* Form source structure */
source_elem(src, SOURCE_ELEM_COMET,
epoch,
incl * DEG_TO_RAD,
anode * DEG_TO_RAD,
perih * DEG_TO_RAD,
aq,
ecc,
0.0,
0.0);
/* Designation */
p = extractstr(line, len, 103, 158);
if(p) {
strncpy(src->name, p, sizeof(src->name)-1);
src->name[sizeof(src->name)-1] = '\0';
}
else
src->name[0] = '\0';
#ifdef TEST
fprintf(stderr, "Got comet '%s': epoch=%lf i=%lf anode=%lf perih=%lf q=%lf e=%lf\n",
src->name, epoch, incl, anode, perih, aq, ecc);
#endif
}
else { /* minor planet */
/* Packed epoch */
p = extractstr(line, len, 21, 25);
yr = packed_cent(p[0]);
if(yr <= 0)
goto error;
yr = (yr * 10 + (p[1] - '0')) * 10 + (p[2] - '0');
mn = packed_md(p[3]);
if(mn < 1 || mn > 12)
goto error;
di = packed_md(p[4]);
if(di < 1 || di > 31)
goto error;
epoch = date2mjd(yr, mn, di); /* convert to MJD(TT) */
/* Elements */
if(extractdouble(line, len, 27, 35, &ma)) /* mean anomaly at epoch, deg */
goto error;
if(extractdouble(line, len, 38, 46, &perih)) /* argument of perihelion, deg */
goto error;
if(extractdouble(line, len, 49, 57, &anode)) /* longitude of ascending node, deg */
goto error;
if(extractdouble(line, len, 60, 68, &incl)) /* inclination, deg */
goto error;
if(extractdouble(line, len, 71, 79, &ecc)) /* eccentricity */
goto error;
if(extractdouble(line, len, 81, 91, &nn)) /* mean motion, deg/day */
goto error;
if(extractdouble(line, len, 93, 103, &aq)) /* semimajor axis, AU */
goto error;
/* Form source structure */
source_elem(src, SOURCE_ELEM_MINOR,
epoch,
incl * DEG_TO_RAD,
anode * DEG_TO_RAD,
perih * DEG_TO_RAD,
aq,
ecc,
ma * DEG_TO_RAD,
nn * DEG_TO_RAD);
/* Designation */
p = extractstr(line, len, 167, 194);
if(p) {
strncpy(src->name, p, sizeof(src->name)-1);
src->name[sizeof(src->name)-1] = '\0';
}
else
src->name[0] = '\0';
#ifdef TEST
fprintf(stderr, "Got MP '%s': epoch=%lf i=%lf anode=%lf perih=%lf a=%lf e=%lf ma=%lf nn=%lf\n",
src->name, epoch, incl, anode, perih, aq, ecc, ma, nn);
#endif
}
return(0);
error:
return(-3);
}
