integer res
real(8) jd0
real(8) dt1, dt2
real(8) PV(6)

jd0 = 2442457
dt1 = 0.5D0
dt2 = 0.9D0

res = calceph_sopen("example1.dat"//C_NULL_CHAR)
if (res.eq.1) then
     ! the heliocentric coordinates of Mars
     res = calceph_scompute(jd0, dt1, 4, 11, PV)
     write (*,*) PV

     res = calceph_scompute(jd0, dt2, 4, 11, PV)
     write (*,*) PV

     call calceph_sclose
endif