int res;
int j;
double jd0=2451624;
double dt1=0.5E0;
double dt2=0.9E0;

double PV[6];
/* open the ephemeris file */
res = calceph_sopen("example1.dat");
if (res)
{
  /* the heliocentric coordinates of Mars */
  calceph_scompute(jd0, dt1, 4, 11, PV);
  for(j=0; j<6; j++) printf("%23.16E\n", PV[j]);

  calceph_scompute(jd0, dt2, 4, 11, PV);
  for(j=0; j<6; j++) printf("%23.16E\n", PV[j]);

  /* close the ephemeris file */
  calceph_sclose();
}