228 lines
5.9 KiB
C
228 lines
5.9 KiB
C
/* > satutl.c
|
|
*
|
|
*/
|
|
|
|
|
|
#include "sgdp4h.h"
|
|
|
|
#include <ctype.h>
|
|
|
|
static char *st_start(char *buf);
|
|
static long i_read(char *str, int start, int stop);
|
|
static double d_read(char *str, int start, int stop);
|
|
|
|
/* ====================================================================
|
|
Read a string from key board, remove CR/LF etc.
|
|
==================================================================== */
|
|
|
|
void read_kb(char *buf)
|
|
{
|
|
int ii;
|
|
|
|
fgets(buf, ST_SIZE-1, stdin);
|
|
|
|
/* Remove the CR/LF etc. */
|
|
for(ii = 0; ii < ST_SIZE; ii++)
|
|
{
|
|
if(buf[ii] == '\r' || buf[ii] == '\n')
|
|
{
|
|
buf[ii] = '\0';
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* ====================================================================
|
|
Read orbit parameters for "satno" in file "filename", return -1 if
|
|
failed to find the corresponding data. Call with satno = 0 to get the
|
|
next elements of whatever sort.
|
|
==================================================================== */
|
|
|
|
int read_twoline(FILE *fp, long search_satno, orbit_t *orb)
|
|
{
|
|
static char search[ST_SIZE];
|
|
static char line1[ST_SIZE];
|
|
static char line2[ST_SIZE];
|
|
char *st1, *st2;
|
|
int found;
|
|
double bm, bx;
|
|
|
|
// Set defaults
|
|
strcpy(orb->desig,"");
|
|
|
|
st1 = line1;
|
|
st2 = line2;
|
|
|
|
do {
|
|
if(fgets(line1, ST_SIZE-1, fp) == NULL)
|
|
return -1;
|
|
st1 = st_start(line1);
|
|
} while(st1[0] != '1');
|
|
|
|
if(search_satno > 0) {
|
|
found = 0;
|
|
} else {
|
|
found = 1;
|
|
search_satno = atol(st1+2);
|
|
}
|
|
sprintf(search, "1 %05ld", search_satno);
|
|
|
|
do {
|
|
st1 = st_start(line1);
|
|
if(strncmp(st1, search, 7) == 0) {
|
|
found = 1;
|
|
break;
|
|
}
|
|
} while(fgets(line1, ST_SIZE-1, fp) != NULL);
|
|
|
|
sprintf(search, "2 %05ld", search_satno);
|
|
|
|
if(found) {
|
|
fgets(line2, ST_SIZE-1, fp);
|
|
st2 = st_start(line2);
|
|
}
|
|
|
|
if(!found || strncmp(st2, search, 7) != 0) {
|
|
return -1;
|
|
}
|
|
orb->ep_year = (int)i_read(st1, 19, 20);
|
|
|
|
if(orb->ep_year < 57) orb->ep_year += 2000;
|
|
else orb->ep_year += 1900;
|
|
|
|
orb->ep_day = d_read(st1, 21, 32);
|
|
|
|
orb->ndot2 = d_read(st1, 34, 43);
|
|
bm = d_read(st1, 45, 50) * 1.0e-5;
|
|
bx = d_read(st1, 51, 52);
|
|
orb->nddot6 = bm * pow(10.0, bx);
|
|
bm = d_read(st1, 54, 59) * 1.0e-5;
|
|
bx = d_read(st1, 60, 61);
|
|
orb->bstar = bm * pow(10.0, bx);
|
|
|
|
orb->eqinc = RAD(d_read(st2, 9, 16));
|
|
orb->ascn = RAD(d_read(st2, 18, 25));
|
|
orb->ecc = d_read(st2, 27, 33) * 1.0e-7;
|
|
orb->argp = RAD(d_read(st2, 35, 42));
|
|
orb->mnan = RAD(d_read(st2, 44, 51));
|
|
orb->rev = d_read(st2, 53, 63);
|
|
orb->norb = i_read(st2, 64, 68);
|
|
|
|
orb->satno = search_satno;
|
|
|
|
// sscanf(st1+9,"%s",orb->desig);
|
|
strncpy(orb->desig,st1+9,8);
|
|
orb->desig[8]='\0';
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* ==================================================================
|
|
Locate the first non-white space character, return location.
|
|
================================================================== */
|
|
|
|
static char *st_start(char *buf)
|
|
{
|
|
if(buf == NULL) return buf;
|
|
|
|
while(*buf != '\0' && isspace(*buf)) buf++;
|
|
|
|
return buf;
|
|
}
|
|
|
|
/* ==================================================================
|
|
Mimick the FORTRAN formatted read (assumes array starts at 1), copy
|
|
characters to buffer then convert.
|
|
================================================================== */
|
|
|
|
static long i_read(char *str, int start, int stop)
|
|
{
|
|
long itmp=0;
|
|
char *buf, *tmp;
|
|
int ii;
|
|
|
|
start--; /* 'C' arrays start at 0 */
|
|
stop--;
|
|
|
|
tmp = buf = (char *)vector(stop-start+2, sizeof(char));
|
|
|
|
for(ii = start; ii <= stop; ii++)
|
|
{
|
|
*tmp++ = str[ii]; /* Copy the characters. */
|
|
}
|
|
*tmp = '\0'; /* NUL terminate */
|
|
|
|
itmp = atol(buf); /* Convert to long integer. */
|
|
free(buf);
|
|
|
|
return itmp;
|
|
}
|
|
|
|
/* ==================================================================
|
|
Mimick the FORTRAN formatted read (assumes array starts at 1), copy
|
|
characters to buffer then convert.
|
|
================================================================== */
|
|
|
|
static double d_read(char *str, int start, int stop)
|
|
{
|
|
double dtmp=0;
|
|
char *buf, *tmp;
|
|
int ii;
|
|
|
|
start--;
|
|
stop--;
|
|
|
|
tmp = buf = (char *)vector(stop-start+2, sizeof(char));
|
|
|
|
for(ii = start; ii <= stop; ii++)
|
|
{
|
|
*tmp++ = str[ii]; /* Copy the characters. */
|
|
}
|
|
*tmp = '\0'; /* NUL terminate */
|
|
|
|
dtmp = atof(buf); /* Convert to long integer. */
|
|
free(buf);
|
|
|
|
return dtmp;
|
|
}
|
|
|
|
/* ==================================================================
|
|
Allocate and check an all-zero array of memory (storage vector).
|
|
================================================================== */
|
|
|
|
void *vector(size_t num, size_t size)
|
|
{
|
|
void *ptr;
|
|
|
|
ptr = calloc(num, size);
|
|
if(ptr == NULL)
|
|
{
|
|
fatal_error("vector: Allocation failed %u * %u", num, size);
|
|
}
|
|
|
|
return ptr;
|
|
}
|
|
|
|
/* ==================================================================
|
|
Print out orbital parameters.
|
|
================================================================== */
|
|
|
|
void print_orb(orbit_t *orb)
|
|
{
|
|
printf("# Satellite ID = %ld\n", (long)orb->satno);
|
|
printf("# Satellite designation = %s\n",orb->desig);
|
|
printf("# Epoch year = %d day = %.8f\n", orb->ep_year, orb->ep_day);
|
|
printf("# Eccentricity = %.7f\n", orb->ecc);
|
|
printf("# Equatorial inclination = %.4f deg\n", DEG(orb->eqinc));
|
|
printf("# Argument of perigee = %.4f deg\n", DEG(orb->argp));
|
|
printf("# Mean anomaly = %.4f deg\n", DEG(orb->mnan));
|
|
printf("# Right Ascension of Ascending Node = %.4f deg\n", DEG(orb->ascn));
|
|
printf("# Mean Motion (number of rev/day) = %.8f\n", orb->rev);
|
|
printf("# First derivative of mean motion = %e\n",orb->ndot2);
|
|
printf("# Second derivative of mean motion = %e\n",orb->nddot6);
|
|
printf("# BSTAR drag = %.4e\n", orb->bstar);
|
|
printf("# Orbit number = %ld\n", orb->norb);
|
|
}
|
|
|
|
/* ====================================================================== */
|