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Add support for ucac5 catalog (#42)

This commit is contained in:
François Meyer 2021-11-29 11:49:29 +00:00 committed by GitHub
parent ff85c47db1
commit 20dd4be6a4
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2 changed files with 191 additions and 4 deletions
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194
GUI/xephem/ucac.c
View File

@ -1,9 +1,9 @@
/* read the UCAC2, 3 or 4 catalog, depending on which index file is found.
/* read the UCAC2, 3, 4 or 5 catalog, depending on which index file is found.
* UCACSetup(): call to change options and base directories.
* UCACFetch(): return an array of ObjF matching the given criteria.
* UCAC2 and 3 stars are in 360 files each .5 deg hi, within 240 bins each
.1 hour RA wide.
* UCAC4 stars are in 900 files each .2 deg hi, within 1440 bins each
* UCAC4 and UCAC5 stars are in 900 files each .2 deg hi, within 1440 bins each
1 minute of RA wide.
*/
@ -41,20 +41,33 @@ typedef struct {
#define ZH (180./NZH) /* zone height, degrees */
/* zones sizes for UCAC4 */
/* source for doc : https://irsa.ipac.caltech.edu/data/UCAC4/readme_u4.txt (checked 20211121)*/
#define NZW4 1440 /* number ra zones wide */
#define ZW4 (24./NZW4) /* zone width, hours */
#define NZH4 900 /* number dec zones hi */
#define ZH4 (180./NZH4) /* zone height, degrees */
/* zones sizes for UCAC5 */
/* source for doc : http://tdc-www.harvard.edu/software/catalogs/ucac5_format.html (checked 20211121)*/
#define NZW5 1440 /* number ra zones wide */
#define ZW5 (24./NZW5) /* zone width, hours */
#define NZH5 900 /* number dec zones hi */
#define ZH5 (180./NZH5) /* zone height, degrees */
#define DPMAS (1.0/3600000.0) /* degrees per milliarcsecond */
typedef XE_UC U2Star[44]; /* UCAC2 record */
typedef XE_UC U3Star[84]; /* UCAC3 record */
typedef XE_UC U4Star[78]; /* UCAC4 record */
typedef XE_UC U5Star[52]; /* UCAC5 record */
static char *basedir; /* full dir with zone files and index */
static FILE *indexfp; /* index file handle */
static FILE *openIndex (char dir[], char msg[], int *ucacvp);
static int add5Bin (ObjFArray *oap, int rz, int dz);
static int read5Index (int rz, int dz, int *nskip, int *nnew);
static int read5Raw (U5Star u[], int dz, int nskip, int nraw);
static void crack5 (U5Star u, int dz, int znm, Obj *op);
static int add4Bin (ObjFArray *oap, int rz, int dz);
static int read4Index (int rz, int dz, int *nskip, int *nnew);
static int read4Raw (U4Star u[], int dz, int nskip, int nraw);
@ -121,7 +134,7 @@ char msg[] /* status or error message if msg[0] != '\0' on return */
int dz; /* scanning dec zone number */
double zw = 0, zh = 0; /* zone width and height */
int nzw = 0, nzh = 0; /* number of zones wide and high */
int ucacv; /* version 2, 3, or 4 */
int ucacv; /* version 2, 3, 4 or 5 */
/* init message */
msg[0] = '\0';
@ -168,6 +181,14 @@ char msg[] /* status or error message if msg[0] != '\0' on return */
nzw = NZW4;
nzh = NZH4;
break;
case 5:
doucac = add5Bin;
zw = ZW5;
zh = ZH5;
nzw = NZW5;
nzh = NZH5;
break;
}
/* init the array.
@ -231,6 +252,164 @@ char msg[] /* status or error message if msg[0] != '\0' on return */
return (oa.n);
}
/* add the stars in the given 0-based ra/dec zone to oap.
* return 0 if ok, else -1
* N.B. rz may wrap
*/
static int
add5Bin (ObjFArray *oap, int rz, int dz)
{
int nskip, nnew;
U5Star *u;
int i;
/* beware of ra wrap */
if (rz < 0)
rz += NZW5;
if (rz >= NZW5)
rz -= NZW5;
/* n stars up through and including this patch */
if (read5Index (rz, dz, &nskip, &nnew) < 0)
return (-1);
/* read the raw star records in this record */
u = malloc (nnew * sizeof(U5Star));
if (!u) {
xe_msg (0, "UCAC: malloc(%d) failed", nnew*sizeof(U5Star));
return (-1);
}
if (read5Raw (u, dz, nskip, nnew) < 0) {
free ((char *)u);
return (-1);
}
/* expand obj memory and crack if interested */
if (oap->mem) {
char *moreobj = realloc (oap->mem, (oap->n + nnew)*sizeof(ObjF));
if (!moreobj) {
xe_msg (0, "UCAC5: malloc failed");
free (u);
return (-1);
}
oap->mem = (ObjF *)moreobj;
for (i = 0; i < nnew; i++)
crack5 (u[i], dz+1, nskip+i+1, (Obj *)(oap->mem + oap->n + i));
}
/* always update count */
oap->n += nnew;
/* ok */
free ((char *)u);
return (0);
}
/* given 0-based ra and dec zone, return number of stars to skip in dec band
* and how many are in the zone.
* return 0 if ok, else -1
*/
static int
read5Index (int rz, int dz, int *nskip, int *nnew)
{
off_t offset;
XE_UC i4[4];
offset = (rz*NZH5 + dz)*sizeof(i4);
if (fseek (indexfp, offset, SEEK_SET) < 0) {
xe_msg (0, "UCAC: index n0 seek %ld: %s", offset, syserrstr());
return (-1);
}
if (fread (i4, sizeof(i4), 1, indexfp) != 1) {
xe_msg (0, "UCAC: index n0 read %d: %s", sizeof(i4), syserrstr());
return (-1);
}
*nskip = I4(i4, 0);
offset = (NZW5*NZH5 + rz*NZH5 + dz)*sizeof(i4);
if (fseek (indexfp, offset, SEEK_SET) < 0) {
xe_msg (0, "UCAC: index nn seek %ld: %s", offset, syserrstr());
return (-1);
}
if (fread (i4, sizeof(i4), 1, indexfp) != 1) {
xe_msg (0, "UCAC: index nn read %d: %s", sizeof(i4), syserrstr());
return (-1);
}
*nnew = I4(i4, 0);
return (0);
}
/* read the nnew raw star records starting after nskip records for the given
* 0-based dec zone.
* return 0 if ok, else -1
*/
static int
read5Raw (U5Star u[], int dz, int nskip, int nnew)
{
char fn[1024];
FILE *fp;
sprintf (fn, "%s/z%03d", basedir, dz+1);
fp = fopen (fn, "r");
if (!fp) {
xe_msg (0, "UCAC: open %s: %s", fn, syserrstr());
return (-1);
}
if (fseek (fp, nskip*sizeof(U5Star), SEEK_SET) < 0) {
xe_msg (0, "UCAC: seek %ld %s: %s", nskip*sizeof(U5Star), fn, syserrstr());
fclose (fp);
return (-1);
}
if (fread (u, sizeof(U5Star), nnew, fp) != nnew) {
xe_msg (0, "UCAC: read %d, %s: %s", sizeof(U5Star), fn, syserrstr());
fclose (fp);
return (-1);
}
fclose (fp);
return (0);
}
/* convert the raw UCAC record into the ObjF portion of op.
* proper motion applied to 2000, libastro::circum.c takes it from there.
*/
static void
crack5 (U5Star u, int dz, int znm, Obj *op)
{
int rawpmra, rawpmdec;
double epu; /* UCAC epoch */
uint64_t srcid=*((uint64_t *)u);
memset (op, 0, sizeof(ObjF)); /* N.B. ObjF, not Obj */
op->o_type = FIXED;
op->f_class = 'S';
op->f_RA = degrad (I4(u,24)*DPMAS); /* ira, UCAC RA at epoch epu */
op->f_dec = degrad (I4(u,28)*DPMAS); /* dcg, UCAC DEC at epoch epu */
op->f_epoch = J2000;
set_fmag (op, I2(u,40)/1000.0); /* Gaia DR1 G magnitude (1/1000 mag) */
epu = I2(u,22)*.001+1997; /* mean UCAC epoch (1/1000 yr after 1997.0) */
rawpmra = I2(u,32); /* .1 mas/yr, on sky */
rawpmdec = I2(u,34); /* .1 mas/yr */
op->f_pmRA = degrad(rawpmra*0.1*DPMAS)/365.25/cos(op->f_dec); /* want RA rad/day */
op->f_pmdec = degrad(rawpmdec*0.1*DPMAS)/365.25; /* want Dec rad/day */
op->f_RA += op->f_pmRA * (2000.0 - epu)*365.25; /* move to 2000 */
op->f_dec += op->f_pmdec * (2000.0 - epu)*365.25; /* move to 2000 */
jkspect (I2(u,46)*0.001, I2(u,50)*0.001, op);
/*
* set id to gaia srcid :
*/
sprintf (op->o_name, "%lu", srcid);
/*
* replace with following line to set id to ucac5 id :
* sprintf (op->o_name, "UCAC5-%03d-%06d", dz, znm);
*/
}
/* add the stars in the given 0-based ra/dec zone to oap.
* return 0 if ok, else -1
* N.B. rz may wrap
@ -728,6 +907,7 @@ openIndex (char dir[], char msg[], int *ucacvp)
static char u2[] = "u2index.da"; /* zone index file name */
static char u3[] = "u3index.unf"; /* zone index file name */
static char u4[] = "u4index.unf"; /* zone index file name */
static char u5[] = "u5index.unf"; /* zone index file name */
char full[1024];
FILE *fp;
@ -746,7 +926,13 @@ openIndex (char dir[], char msg[], int *ucacvp)
if (fp) {
*ucacvp = 4;
} else {
sprintf (msg, "Can not find %s or %s or %s", u2, u3, u4);
sprintf (full, "%s/%s", dir, u5);
fp = fopen (full, "r");
if (fp) {
*ucacvp = 5;
} else {
sprintf (msg, "Can not find %s or %s or %s or %s", u2, u3, u4, u5);
}
}
}
}

1
libastro/astro.h
View File

@ -50,6 +50,7 @@ typedef enum {
*/
#define MJD0 2415020.0
#define J2000 (2451545.0 - MJD0) /* yes, 2000 January 1 at 12h */
#define J2015 (2457024.0 - MJD0)
/* the Now and Obj typedefs.
* also, a few miscellaneous constants and declarations.