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/*
* test2.cpp 5 July 2002
*
* A skeleton main() function to demonstrate the use of
* the various NORAD ephemerides. It reads in the file
* 'test.tle' and computes ephemerides at assorted times for
* all elements in the file. The times used, and the choice
* of SxP4 vs. SxP8, can be switched with various keywords in
* the 'test.tle' file. The result should match 'test2.txt'.
*/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include "norad.h"
/* Main program */
int main( int argc, char **argv)
{
double vel[3], pos[3]; /* Satellite position and velocity vectors */
FILE *ifile = fopen( (argc == 1) ? "test.tle" : argv[1], "rb");
tle_t tle; /* Pointer to two-line elements set for satellite */
char line1[100], line2[100];
int n_times = 5, dundee_output = 0;
double times[400];
int ephem = TLE_EPHEMERIS_TYPE_SGP4; /* default to SGP4 */
int i; /* Index for loops etc */
for( i = 2; i < argc; i++)
switch( argv[i][0])
{
case 's': case 'S':
sxpx_set_dpsec_integration_step( atof( argv[i] + 1));
break;
case 'd': case 'D':
sxpx_set_implementation_param( SXPX_DUNDEE_COMPLIANCE, 1);
break;
case 'o': case 'O':
{
const int new_order = atoi( argv[i] + 1);
sxpx_set_implementation_param(
SXPX_DPSEC_INTEGRATION_ORDER, new_order);
printf( "Set to order %d\n", new_order);
}
break;
default:
break;
}
if( !ifile)
{
printf( "Couldn't open input TLE file\n");
exit( -1);
}
for( i = 0; i < n_times; i++)
times[i] = (double)(i * 30);
if( fgets( line1, sizeof( line1), ifile))
while( fgets( line2, sizeof( line2), ifile))
{
if( !memcmp( line2, "Ephem ", 6))
ephem = (line2[6] - '0');
else if( !memcmp( line2, "Dundee ", 7))
{
double t0, step;
sscanf( line2 + 7, "%lf %lf %d", &t0, &step, &n_times);
for( i = 0; i < n_times; i++)
times[i] = t0 + (double)i * step;
sxpx_set_implementation_param( SXPX_DUNDEE_COMPLIANCE, 1);
dundee_output = 1;
}
else if( !memcmp( line2, "Times: ", 7))
{
int loc = 7, bytes_read;
n_times = 0;
while( sscanf( line2 + loc, "%lf%n", times + n_times, &bytes_read) == 1)
{
loc += bytes_read;
n_times++;
}
}
else if( parse_elements( line1, line2, &tle) >= 0)
{ /* hey! we got a TLE! */
int is_deep = select_ephemeris( &tle);
const char *ephem_names[6] = { "???", "SGP ", "SGP4", "SDP4", "SGP8", "SDP8" };
double sat_params[N_SAT_PARAMS];
if( is_deep)
if( ephem == TLE_EPHEMERIS_TYPE_SGP4 || ephem == TLE_EPHEMERIS_TYPE_SGP8)
ephem++; /* switch to an SDPx model */
if( !is_deep)
if( ephem == TLE_EPHEMERIS_TYPE_SDP4 || ephem == TLE_EPHEMERIS_TYPE_SDP8)
ephem--; /* switch to an SGPx model */
line1[69] = line2[69] = '\0';
if( dundee_output)
printf( "#%s\n#%s\n", line1, line2);
else
printf( "%s\n%s\n", line1, line2);
if( is_deep)
printf("Deep-Space type Ephemeris (%s) selected:",
ephem_names[ephem]);
else
printf("Near-Earth type Ephemeris (%s) selected:",
ephem_names[ephem]);
/* Print some titles for the results */
printf("\nEphem:%s Tsince "
"X/Xdot Y/Ydot Z/Zdot\n", ephem_names[ephem]);
/* Calling of NORAD routines */
/* Each NORAD routine (SGP, SGP4, SGP8, SDP4, SDP8) */
/* will be called in turn with the appropriate TLE set */
switch( ephem)
{
case TLE_EPHEMERIS_TYPE_SGP:
SGP_init( sat_params, &tle);
break;
case TLE_EPHEMERIS_TYPE_SGP4:
SGP4_init( sat_params, &tle);
break;
case TLE_EPHEMERIS_TYPE_SGP8:
SGP8_init( sat_params, &tle);
break;
case TLE_EPHEMERIS_TYPE_SDP4:
SDP4_init( sat_params, &tle);
break;
case TLE_EPHEMERIS_TYPE_SDP8:
SDP8_init( sat_params, &tle);
break;
}
for( i = 0; i < n_times; i++)
{
switch( ephem)
{
case TLE_EPHEMERIS_TYPE_SGP:
SGP(times[i], &tle, sat_params, pos, vel);
break;
case TLE_EPHEMERIS_TYPE_SGP4:
SGP4(times[i], &tle, sat_params, pos, vel);
break;
case TLE_EPHEMERIS_TYPE_SGP8:
SGP8(times[i], &tle, sat_params, pos, vel);
break;
case TLE_EPHEMERIS_TYPE_SDP4:
SDP4(times[i], &tle, sat_params, pos, vel);
break;
case TLE_EPHEMERIS_TYPE_SDP8:
SDP8(times[i], &tle, sat_params, pos, vel);
break;
}
/* Calculate and print results */
vel[0] /= 60.; /* cvt km/minute to km/second */
vel[1] /= 60.;
vel[2] /= 60.;
if( dundee_output)
{
printf("%12.4f %16.8f %16.8f %16.8f",
times[i],pos[0],pos[1],pos[2]);
printf(" %16.8f %16.8f %16.8f\n",
vel[0],vel[1],vel[2]);
}
else
{
printf("%5d %12.4f %16.8f %16.8f %16.8f\n", tle.norad_number,
times[i],pos[0],pos[1],pos[2]);
printf(" %16.8f %16.8f %16.8f\n",
vel[0],vel[1],vel[2]);
}
} /* End of for( i = 0; i < n_times; i++) */
printf( "\n");
}
strcpy( line1, line2);
}
fclose( ifile);
return(0);
} /* End of main() */
/*------------------------------------------------------------------*/
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