Ephemeris* PlatformPosition::Interpolate(JSDDateTime date) const
{
const double JOURCIVIL_LENGTH = 86400.0;
Ephemeris* ephem = NULL;
if (_nbrData <= 1)
{
return NULL;
}
/*
* The first element of the list is cloned to ensure that the
* output ephemeris is expressed in the same coordinate system as
* input ones
*/
ephem = _data[0]->Clone();
/* NORMAL CASE */
/*------------*/
double dt = 0.0;
if (ephem != NULL)
{
ephem->set_date(date);
dt = (date.get_day0hTU().get_julianDate()
- _data[0]->get_date().get_day0hTU().get_julianDate())
* JOURCIVIL_LENGTH
+ date.get_second() - _data[0]->get_date().get_second()
+ date.get_decimal() - _data[0]->get_date().get_decimal();
/* Computation by Everett */
/*---------------------*/
double pos[3];
double speed[3];
for (int j = 0; j < 3; j++)
{
_interpolator[j]->Interpolate(dt, pos[j], speed[j]);
}
ephem->set_position(pos);
ephem->set_speed(speed);
}
return ephem;
}
