File: actread.c

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/*** File libwcs/actread.c
 *** January 11, 2001
 *** By Doug Mink, dmink@cfa.harvard.edh
 *** Harvard-Smithsonian Center for Astrophysics
 */

#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include "fitsfile.h"
#include "vimoswcs.h"
#include "vimoswcscat.h"

/* pathname of ACT CDROM or catalog search engine URL */
char actcd[64]="/data/act";

static int actreg();
struct StarCat *actopen();
void actclose();
static int actstar();
static int actsize();
static int actsra();

/* ACTREAD -- Read USNO ACT Star Catalog stars from CDROM */

int
actread (cra,cdec,dra,ddec,drad,distsort,sysout,eqout,epout,mag1,mag2,nstarmax,
	 gnum,gra,gdec,gpra,gpdec,gmag,gmagb,gtype,nlog)

double	cra;		/* Search center J2000 right ascension in degrees */
double	cdec;		/* Search center J2000 declination in degrees */
double	dra;		/* Search half width in right ascension in degrees */
double	ddec;		/* Search half-width in declination in degrees */
double	drad;		/* Limiting separation in degrees (ignore if 0) */
int	distsort;	/* 1 to sort stars by distance from center */
int	sysout;		/* Search coordinate system */
double	eqout;		/* Search coordinate equinox */
double	epout;		/* Proper motion epoch (0.0 for no proper motion) */
double	mag1,mag2;	/* Limiting magnitudes (none if equal) */
int	nstarmax;	/* Maximum number of stars to be returned */
double	*gnum;		/* Array of Guide Star numbers (returned) */
double	*gra;		/* Array of right ascensions (returned) */
double	*gdec;		/* Array of declinations (returned) */
double  *gpra;          /* Array of right ascension proper motions (returned) */
double  *gpdec;         /* Array of declination proper motions (returned) */
double	*gmag;		/* Array of visual magnitudes (returned) */
double	*gmagb;		/* Array of blue magnitudes (returned) */
int	*gtype;		/* Array of object types (returned) */
int	nlog;		/* 1 for diagnostics */
{
    double ra1,ra2;	/* Limiting right ascensions of region in degrees */
    double dec1,dec2;	/* Limiting declinations of region in degrees */
    double dist = 0.0;  /* Distance from search center in degrees */
    double faintmag=0.0; /* Faintest magnitude */
    double maxdist=0.0; /* Largest distance */
    int	faintstar=0;	/* Faintest star */
    int	farstar=0;	/* Most distant star */
    double *gdist;	/* Array of distances to stars */
    int nreg;		/* Number of ACT regions in search */
    int rlist[100];	/* List of input region files */
    int sysref=VIMOSWCS_J2000;	/* Catalog coordinate system */
    double eqref=2000.0;	/* Catalog equinox */
    double epref=2000.0;	/* Catalog epoch */
    struct StarCat *starcat;
    struct Star *star;
    int verbose;
    int wrap;
    int rnum, ireg;
    int jstar, iw;
    int nrmax,nstar,i, ntot;
    int istar, istar1, istar2, isp;
    double num, ra, dec, rapm, decpm, mag, magb;
    double rra1, rra2, rra2a, rdec1, rdec2;
    char *str;
    char cstr[32];
    int nbytes;

    ntot = 0;
    gdist = NULL;
    if (nlog == 1)
	verbose = 1;
    else
	verbose = 0;

    /* Set path to ACT Catalog */
    if ((str = getenv("ACT_PATH")) != NULL ) {

	/* If pathname is a URL, search and return */
	if (!strncmp (str, "http:",5)) {
	    return (webread (str,"act",distsort,cra,cdec,dra,ddec,drad,
			     sysout,eqout,epout,mag1,mag2,nstarmax,
			     gnum,gra,gdec,gpra,gpdec,gmag,gmagb,gtype,nlog));
	    }
	}
    if (!strncmp (actcd, "http:",5)) {
	return (webread (actcd,"act",distsort,cra,cdec,dra,ddec,drad,
			 sysout,eqout,epout,mag1,mag2,nstarmax,
			 gnum,gra,gdec,gpra,gpdec,gmag,gmagb,gtype,nlog));
	}

    vimoswcscstr (cstr, sysout, eqout, epout);

    SearchLim (cra, cdec, dra, ddec, sysout, &ra1, &ra2, &dec1, &dec2, verbose);

/* If RA range includes zero, split it in two */
    wrap = 0;
    if (ra1 > ra2)
	wrap = 1;
    else
	wrap = 0;

/* make mag1 always the smallest magnitude */
    if (mag2 < mag1) {
	mag = mag2;
	mag2 = mag1;
	mag1 = mag;
	}

    /* Allocate table for distances of stars from search center */
    if (nstarmax > 10)
	nbytes = nstarmax * sizeof (double);
    else
	nbytes = 10 * sizeof (double);
    gdist = (double *) malloc (nbytes);

    /* Allocate catalog entry buffer */
    star = (struct Star *) calloc (1, sizeof (struct Star));
    star->num = 0.0;

    nstar = 0;
    jstar = 0;

    rra1 = ra1;
    rra2 = ra2;
    rdec1 = dec1;
    rdec2 = dec2;
    RefLim (cra, cdec, dra, ddec, sysout, sysref, eqout, eqref, epout,
	    &rra1, &rra2, &rdec1, &rdec2, verbose);
    if (rra1 > rra2) {
	rra2a = rra2;
	rra2 = 360.0;
	if (!wrap) wrap = 1;
	}
    nrmax = 100;

    /* If searching through RA = 0:00, split search in two */
    for (iw = 0; iw <= wrap; iw++) {

	/* Find ACT Star Catalog regions in which to search */
	nreg = actreg (rra1,rra2,rdec1,rdec2,nrmax,rlist,verbose);
	if (nreg <= 0) {
	    fprintf (stderr,"ACTREAD:  no ACT regions found\n");
	    free ((void *)gdist);
	    free ((void *)star);
	    return (0);
	    }

	/* Loop through region list */
	for (ireg = 0; ireg < nreg; ireg++) {

	    /* Open catalog file for this region */
	    starcat = actopen (rlist[ireg]);
	    rnum = rlist[ireg];

	    /* Set first and last stars to check */
	    istar1 = actsra (starcat, star, rra1);
	    istar2 = actsra (starcat, star, rra2);
	    if (verbose)
		fprintf (stderr,"ACTREAD: Searching stars %d.%d through %d.%d\n",
			rnum,istar1,rnum,istar2);

	    /* Loop through catalog for this region */
	    for (istar = istar1; istar <= istar2; istar++) {
		if (actstar (starcat, star, istar)) {
		    fprintf (stderr,"ACTREAD: Cannot read star %d\n", istar);
		    break;
		    }

		/* ID number */
		num = (double) rlist[ireg] + (star->num / 100000.0);

		/* Get position in output coordinate system, equinox, epoch */
		rapm = star->rapm;
		decpm = star->decpm;
		ra = star->ra;
		dec = star->dec;
		vimoswcsconp (sysref, sysout, eqref, eqout, epref, epout,
		 	 &ra, &dec, &rapm, &decpm);

		/* Magnitude */
		mag = star->xmag[0];
		magb = star->xmag[1];

		/* Spectral Type */
		isp = (1000 * (int) star->isp[0]) + (int)star->isp[1];

		/* Compute distance from search center */
		if (drad > 0 || distsort)
		    dist = vimoswcsdist (cra,cdec,ra,dec);
		else
		    dist = 0.0;

		/* Check magnitude and position limits */
		if ((mag1 == mag2 || (mag >= mag1 && mag <= mag2)) &&
		    ((wrap && (ra <= ra1 || ra >= ra2)) ||
		    (!wrap && (ra >= ra1 && ra <= ra2))) &&
		    ((drad > 0.0 && dist <= drad) ||
     		    (drad == 0.0 && dec >= dec1 && dec <= dec2))) {

		    /* Save star position and magnitude in table */
		    if (nstar < nstarmax) {
			gnum[nstar] = num;
			gra[nstar] = ra;
			gdec[nstar] = dec;
			gpra[nstar] = rapm;
			gpdec[nstar] = decpm;
			gmag[nstar] = mag;
			gmagb[nstar] = magb;
			gtype[nstar] = isp;
			gdist[nstar] = dist;
			if (dist > maxdist) {
			    maxdist = dist;
			    farstar = nstar;
			    }
			if (mag > faintmag) {
			    faintmag = mag;
			    faintstar = nstar;
			    }
			}

		    /* If too many stars and distance sorting,
		       replace farthest star */
		    else if (distsort) {
			if (dist < maxdist) {
			    gnum[farstar] = num;
			    gra[farstar] = ra;
			    gdec[farstar] = dec;
			    gpra[farstar] = rapm;
			    gpdec[farstar] = decpm;
			    gmag[farstar] = mag;
			    gmagb[farstar] = magb;
			    gtype[farstar] = isp;
			    gdist[farstar] = dist;

			    /* Find new farthest star */
			    maxdist = 0.0;
			    for (i = 0; i < nstarmax; i++) {
				if (gdist[i] > maxdist) {
				    maxdist = gdist[i];
				    farstar = i;
				    }
				}
			    }
			}

		    /* Else if too many stars, replace faintest star */
		    else if (mag < faintmag) {
			gnum[faintstar] = num;
			gra[faintstar] = ra;
			gdec[faintstar] = dec;
			gpra[farstar] = rapm;
			gpdec[farstar] = decpm;
			gmag[faintstar] = mag;
			gmagb[faintstar] = magb;
			gtype[faintstar] = isp;
			gdist[faintstar] = dist;
			faintmag = 0.0;

			/* Find new faintest star */
			for (i = 0; i < nstarmax; i++) {
			    if (gmag[i] > faintmag) {
				faintmag = gmag[i];
				faintstar = i;
				}
			    }
			}

		    nstar++;
		    if (nlog == 1)
			fprintf (stderr,"ACTREAD: %11.6f: %9.5f %9.5f %5.2f %5.2f\n",
				 num,ra,dec,magb,mag);

		    /* End of accepted star processing */
		    }

		/* Log operation */
		jstar++;
		if (nlog > 0 && istar%nlog == 0)
		    fprintf (stderr,"ACTREAD: %5d / %5d / %5d sources\r",
			     nstar,jstar,starcat->nstars);

		/* End of star loop */
		}

	    ntot = ntot + starcat->nstars;
	    if (nlog > 0)
		fprintf (stderr,"ACTREAD: %4d / %4d: %5d / %5d  / %5d sources from region %4d    \n",
		 	 ireg+1,nreg,nstar,jstar,starcat->nstars,rlist[ireg]);

	    /* Close region input file */
	    actclose (starcat);
	    }
	rra1 = 0.0;
	rra2 = rra2a;
	}

/* close output file and summarize transfer */
    if (nlog > 0) {
	if (nreg > 1)
	    fprintf (stderr,"ACTREAD: %d regions: %d / %d found\n",nreg,nstar,ntot);
	else
	    fprintf (stderr,"ACTREAD: 1 region: %d / %d found\n",nstar,ntot);
	if (nstar > nstarmax)
	    fprintf (stderr,"ACTREAD: %d stars found; only %d returned\n",
		     nstar,nstarmax);
	}
    free ((void *)star);
    free ((void *)gdist);
    return (nstar);
}

/* ACTRNUM -- Read HST Guide Star Catalog stars from CDROM */

int
actrnum (nstars,sysout,eqout,epout,
	 gnum,gra,gdec,gpra,gpdec,gmag,gmagb,gtype,nlog)

int	nstars;		/* Number of stars to find */
int	sysout;		/* Search coordinate system */
double	eqout;		/* Search coordinate equinox */
double	epout;		/* Proper motion epoch (0.0 for no proper motion) */
double	*gnum;		/* Array of Guide Star numbers (returned) */
double	*gra;		/* Array of right ascensions (returned) */
double	*gdec;		/* Array of declinations (returned) */
double  *gpra;          /* Array of right ascension proper motions (returned) */
double  *gpdec;         /* Array of declination proper motions (returned) */
double	*gmag;		/* Array of V magnitudes (returned) */
double	*gmagb;		/* Array of B magnitudes (returned) */
int	*gtype;		/* Array of object types (returned) */
int	nlog;		/* 1 for diagnostics */
{
    int sysref;		/* Catalog coordinate system */
    double eqref;	/* Catalog equinox */
    double epref;	/* Catalog epoch */
    struct StarCat *starcat;
    struct Star *star;

    int rnum;
    int jstar;
    int istar, nstar, snum, isp;
    double num, ra, dec, rapm, decpm, mag, magb;
    char *str;

    /* Set path to ACT Catalog */
    if ((str = getenv("ACT_PATH")) != NULL ) {

	/* If pathname is a URL, search and return */
	if (!strncmp (str, "http:",5)) {
	    return (webrnum (str,"act",nstars, sysout,eqout,epout,
			     gnum,gra,gdec,gpra,gpdec,gmag,gmagb,gtype,nlog));
	    }
	}
    if (!strncmp (actcd, "http:",5)) {
	return (webrnum (actcd,"act",nstars, sysout,eqout,epout,
			 gnum,gra,gdec,gpra,gpdec,gmag,gmagb,gtype,nlog));
	}

    /* Allocate catalog entry buffer */
    star = (struct Star *) calloc (1, sizeof (struct Star));
    star->num = 0.0;

    nstar = 0;

/* Loop through star list */
    for (jstar = 0; jstar < nstars; jstar++) {
	rnum = (int) gnum[jstar];
	snum = (int) (((gnum[jstar] - (double)rnum) * 100000.0) + 0.01);

	/* Open file for this region of ACT catalog */
	starcat = actopen (rnum);
	if (starcat == NULL) {
	    free ((void*) star);
	    return (0);
	    }

	sysref = starcat->coorsys;
	eqref = starcat->equinox;
	epref = starcat->epoch;

	/* Find star in catalog */
	istar = snum;
	if (actstar (starcat, star, istar)) {
	    fprintf (stderr,"ACTRNUM: Cannot read star %d\n", istar);
	    gra[nstar] = 0.0;
	    gdec[nstar] = 0.0;
	    gmag[nstar] = 0.0;
	    gmagb[nstar] = 0.0;
	    gtype[nstar] = 0;
	    continue;
	    }

	/* If star has been found in catalog */

	/* ID number */
	num = star->num;

	/* Position in degrees at designated epoch */
	ra = star->ra;
	dec = star->dec;
	rapm = star->rapm;
	decpm = star->decpm;
	vimoswcsconp (sysref, sysout, eqref, eqout, epref, epout,
		     &ra, &dec, &rapm, &decpm);

	/* Magnitude */
	mag = star->xmag[0];
	magb = star->xmag[1];

	/* Spectral Type */
	isp = (1000 * (int) star->isp[0]) + (int)star->isp[1];

	/* Save star position and magnitude in table */
	gra[nstar] = ra;
	gdec[nstar] = dec;
	gpra[nstar] = rapm;
	gpdec[nstar] = decpm;
	gmag[nstar] = mag;
	gmagb[nstar] = magb;
	gtype[nstar] = isp;
	nstar++;
	if (nlog == 1)
	    fprintf (stderr,"ACTRNUM: %11.6f: %9.5f %9.5f %5.2f %5.2f %s  \n",
		     num, ra, dec, magb, mag, star->isp);

	/* End of star loop */
	}

/* Summarize search */
    if (nlog > 0)
	fprintf (stderr,"ACTRNUM: %d / %d found\n",nstar,starcat->nstars);

    actclose (starcat);
    free ((void*) star);
    return (nstar);
}


/* ACTREG -- from RA and Dec ranges, figure out which ACT files to search
 * Build a list containing the numeric part of the CDROM file names.
 */

static int regions[48]={   0,  30, 100, 130, 200, 230, 300, 330, 400, 430,
			 500, 530, 600, 630, 700, 730, 800, 830, 900, 930,
			1000,1030,1100,1130,1200,1230,1300,1330,1400,1430,
			1500,1530,1600,1630,1700,1730,1800,1830,1900,1930,
			2000,2030,2100,2130,2200,2230,2300,2330};
static double reghour[49]={ 0.0, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5,
			    5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5,
			   10.0,10.5,11.0,11.5,12.0,12.5,13.0,13.5,14.0,14.5,
			   15.0,15.5,16.0,16.5,17.0,17.5,18.0,18.5,19.0,19.5,
			   20.0,20.5,21.0,21.5,22.0,22.5,23.0,23.5,24.0};

static int
actreg (ra1, ra2, dec1, dec2, nrmax, rgns, verbose)

double	ra1, ra2;	/* Right ascension limits in degrees */
double	dec1, dec2; 	/* Declination limits in degrees */
int	nrmax;		/* Maximum number of regions to find */
int	*rgns;		/* Region numbers (returned)*/
int	verbose;	/* 1 for diagnostics */

{
    int nsrch;		/* Number of regions found (returned) */

    int i, ir, irx, ir1, ir2;

    /* Zero out regions to be searched */
    for (i = 0; i < nrmax; i++)
	rgns[i] = 0;

    /* Find region range to search based on declination */

    /* Find RA regions to search */
    ra1 = ra1 / 15.0;
    ra2 = ra2 / 15.0;
    irx = 0;

    /* Find first region to search */
    for (ir = 1; ir < 49; ir++) {
	if (ra1 >= reghour[ir-1] && ra1 <= reghour[ir]) {
	    ir1 = ir - 1;
	    break;
	    }
	}

    /* Find last region to search */
    for (ir = 1; ir < 49; ir++) {
	if (ra2 >= reghour[ir-1] && ra2 <= reghour[ir]) {
	    ir2 = ir - 1;
	    break;
	    }
	}

    if (ir2 >= ir1) {
	for (ir = ir1; ir <= ir2; ir++) {
	    if (irx < nrmax)
		rgns[irx++] = regions[ir];
	    }
	}
    else if (ir2 < ir1) {
	for (ir = ir1; ir < 48; ir++) {
	    if (irx < nrmax)
		rgns[irx++] = regions[ir];
	    }
	for (ir = 0; ir <= ir2; ir++) {
	    if (irx < nrmax)
		rgns[irx++] = regions[ir];
	    }
	}
    nsrch = irx;

    if (verbose) {
	fprintf (stderr,"ACTREG: RA: %.5f - %.5f, Dec: %.5f - %.5f\n",
		 ra1,ra2,dec1,dec2);
	fprintf (stderr,"ACTREG: searching %d regions:",nsrch);
	for (ir = 0; ir < nsrch; ir++)
	    fprintf (stderr," %04d",rgns[ir]);
	fprintf (stderr,"\n");
	}
    return (nsrch);
}


/* ACTOPEN -- Open ACT catalog region file, returning number of entries */

struct StarCat *
actopen (regnum)

int regnum;	/* ACT Catalog region number */

{
    FILE *fcat;
    struct StarCat *sc;
    int lfile, lpath;
    char *actfile;
    char *path;		/* Full pathname for catalog file */
/*    static int actsize();  */
    char *cdpath;

    /* Set the pathname using the appropriate ACT CDROM directory */
    if ((cdpath = getenv("ACT_PATH")) == NULL )
	cdpath = actcd;
    lpath = strlen (cdpath) + 32;
    path = (char *) calloc (lpath, 1);

    /* Declination zoned regions */
    if (regnum > 0 && regnum < 5)
	sprintf (path,"%s/data2/act%1d.dat", cdpath, regnum);

    /* Right ascension zoned regions */
    else
	sprintf (path,"%s/data1/act%04d.dat", cdpath, regnum);

    /* Find length of ACT catalog region file */
    lfile = actsize (path);

    /* Check for existence of catalog */
    if (lfile < 2) {
	fprintf (stderr,"ACTOPEN: Binary catalog %s has no entries\n", path);
	free (path);
	return (0);
	}

    /* Open ACT region file */
    if (!(fcat = fopen (path, "r"))) {
	fprintf (stderr,"ACTOPEN: ACT region file %s cannot be read\n",path);
	free (path);
	return (0);
	}

    /* Set ACT catalog header information */
    sc = (struct StarCat *) calloc (1, sizeof (struct StarCat));
    sc->byteswapped = 0;

    sc->nbent = 161;
    sc->nstars = lfile / sc->nbent;

    /* Separate filename from pathname and save in structure */
    actfile = strrchr (path,'/');
    if (actfile)
	actfile = actfile + 1;
    else
	actfile = path;
    if (strlen (actfile) < 24)
	strcpy (sc->isfil, actfile);
    else
	strncpy (sc->isfil, actfile, 23);

    /* Set other catalog information in structure */
    sc->inform = 'J';
    sc->coorsys = VIMOSWCS_J2000;
    sc->epoch = 2000.0;
    sc->equinox = 2000.0;
    sc->ifcat = fcat;
    sc->sptype = 2;

    /* ACT region files are all RA-sorted */
    sc->rasorted = 1;

    return (sc);
}


void
actclose (sc)
struct StarCat *sc;	/* Star catalog descriptor */
{
    fclose (sc->ifcat);
    free ((void *)sc);
    return;
}


/* ACTSRA -- Find star closest to given RA in ACT catalog file */

static int
actsra (sc, st, dra)

struct StarCat *sc;	/* Star catalog descriptor */
struct Star *st;	/* Current star entry */
double	dra;		/* Right ascension in degrees */

{
    char rastr[16], raxstr[16], ramins[16], ramaxs[16];
    int istar0, istarx, nrep, ismin, ismax;
    double rax, ramin, ramax;
    int verbose = 0;

    /* Keep RA between 0 and 360 degrees */
    if (dra > 360.0)
	rax = dra - 360.0;
    else
	rax = dra;

    ismin = 1;
    if (actstar (sc, st, ismin)) {
	fprintf (stderr,"ACTSRA: Cannot read star %d\n", ismin);
	return (0);
	}
    else
	ramin = st->ra;

    ismax = sc->nstars;
    if (actstar (sc, st, ismax)) {
	fprintf (stderr,"ACTSRA: Cannot read star %d\n", ismax);
	return (0);
	}
    else
	ramax = st->ra;

    istarx = sc->nstars / 2;

    for (nrep = 0; nrep < 32; nrep++) {
	if (actstar (sc, st, istarx)) {
	    fprintf (stderr,"ACTSRA: Cannot read star %d\n", istarx);
            return (0);
	    }

	/* Find next catalog number to read */
	if (st->ra < rax) {
	    ismin = istarx;
	    ramin = st->ra;
	    istar0 = istarx;
	    if (ismax - istarx > 1)
		istarx = istarx + (ismax - istarx) / 2;
	    else if (ismax - istarx > 0)
		istarx = istarx + 1;
	    }
	else if (st->ra > rax) {
	    ismax = istarx;
	    ramax = st->ra;
	    istar0 = istarx;
	    if (istarx - ismin > 1)
		istarx = istarx - ((istarx - ismin) / 2);
	    else if (istarx - ismin > 0)
		istarx = istarx - 1;
	    }
	else
	    break;

	if (verbose) {
	    ra2str (rastr, 16, st->ra, 3);
	    ra2str (raxstr, 16, rax, 3);
	    ra2str (ramins, 16, ramin, 3);
	    ra2str (ramaxs, 16, ramax, 3);
	    fprintf (stderr,"%9d: %s -> %s  %9d: %s  %9d: %s\n",
		    istarx, rastr, raxstr, ismin,ramins,ismax,ramaxs);
	    }
	if (istarx == istar0)
	    break;
	}

    /* Make sure final star is real */
    if (actstar (sc, st, istarx)) {
	fprintf (stderr,"ACTSRA: Cannot read star %d\n", istarx);
        return (0);
	}
    else
	return (istarx);
}


/* ACTSTAR -- Get ACT catalog entry for one star;
              return 0 if successful */

static int
actstar (sc, st, istar)

struct StarCat *sc;	/* Star catalog descriptor */
struct Star *st;	/* Current star entry */
int istar;	/* Star sequence number in ACT catalog region file */
{
    int nbr;
    long offset;
    char dsgn;
    char line[256];
    int irh,irm,idd,idm;
    double rs, ds, bvmag;

    /* Drop out if catalog pointer is not set */
    if (sc == NULL)
	return (1);

    /* Drop out if catalog is not open */
    if (sc->ifcat == NULL)
	return (2);

    /* Drop out if star number is too large */
    if (istar > sc->nstars) {
	fprintf (stderr, "ACTSTAR:  %d  > %d is not in catalog\n",
		 istar, sc->nstars);
	return (3);
	}

    /* Move file pointer to start of correct star entry */
    if (istar > 0) {
	offset = (istar - 1) * sc->nbent;
	if (fseek (sc->ifcat, offset, SEEK_SET))
	    return (4);
	}

    /* Read catalog entry */
    if ((nbr = fread (line, sc->nbent, 1, sc->ifcat)) > sc->nbent) {
	fprintf (stderr, "ACTSTAR:  %d / %d bytes read from %s\n",
		 nbr, sc->nbent, sc->isfil);
	return (5);
	}

    st->num = (double) istar;

    /* Read position for this star */
    irh = atoi (line);
    irm = atoi (line+3);
    rs = atof (line+6);
    dsgn = line[14];
    idd = atoi (line+15);
    idm = atoi (line+18);
    ds = atof (line+21);

    /* Convert position to degrees */
    st->ra = hrdeg ((double)irh + ((double)irm)/60.0 + rs / 3600.0);
    st->dec = (double) idd + ((double)idm) / 60.0 + ds / 3600.0;
    if (dsgn == '-') st->dec = -st->dec;

    /* Read proper motion and convert it to to degrees/year */
    st->rapm = hrdeg (atof (line+28)) / 3600.0;
    st->decpm = atof (line+36) / 3600.0;

    /* Set V, B, B-V magnitudes */
    st->xmag[0] = atof (line+75);
    st->xmag[1] = atof (line+68);
    st->xmag[2] = atof (line+82);

    /* Set main sequence spectral type */
    bvmag = st->xmag[2];
    bv2sp (&bvmag, 0.0, 0.0, st->isp);

    return (0);
}

/* ACTSIZE -- return size of one ACT catalog file in bytes */

static int
actsize (filename)

char	*filename;	/* Name of file for which to find size */
{
    FILE *diskfile;
    long filesize;

    /* Open file */
    if ((diskfile = fopen (filename, "r")) == NULL)
	return (-1);

    /* Move to end of the file */
    if (fseek (diskfile, 0, 2) == 0)

	/* Position is the size of the file */
	filesize = ftell (diskfile);

    else
	filesize = -1;

    fclose (diskfile);

    return (filesize);
}


/* Feb 11 1999	New program
 * Apr 13 1999	Fix bugs which caused failure on crossing 0:00 h
 * May 12 1999	Fix bug for all searches
 * May 21 1999	Fix bug with proper motion so it is in deg/yr, not sec/yr
 * Jun 16 1999	Use SearchLim()
 * Aug 16 1999	Add RefLim() to get converted search coordinates right
 * Aug 25 1999	Return real number of stars from actread()
 * Sep 16 1999	Fix bug which didn't always return closest stars
 * Sep 16 1999	Add distsort argument so brightest stars in circle works, too
 * Oct 21 1999	Delete unused varaiables after lint
 *
 * Jan  5 2000	Add 2 to spectral type string so there can be proper termination
 * Mar 15 2000	Add proper motions to returns from actread() and actrnum()
 * May 31 2000	Get spectral type from bv2sp()
 * Jun  2 2000	Free all allocated data structures
 * Jun  9 2000	Fix bug which caused memory overflow if limiting number
 * Jun 26 2000	Add coordinate system to SearchLim() arguments
 * Sep 25 2000	Set sc->sptype to 2 to indicate presence of spectral type
 * Nov 29 2000	Add option to read catalog using HTTP
 * Dec 11 2000	Allow catalog search engine URL in actcd[]
 *
 * Jan 11 2001	All printing is to stderr
 */