Keplerian Orbits

radvel.kepler.kepler(inbigM, inecc)[source]

Solve Kepler’s Equation

Parameters:
  • inbigM (array) – input Mean anomaly
  • inecc (array) – eccentricity
Returns:

array

Return type:

eccentric anomaly

radvel.kepler.rv_drive(t, orbel, use_c_kepler_solver=True)[source]

RV Drive

Parameters:
  • t (array of floats) – times of observations
  • orbel (array of floats) – [per, tp, e, om, K]. Omega is expected to be in radians
  • use_c_kepler_solver (bool) – (default: True) If True use the Kepler solver written in C, else use the Python/NumPy version.
Returns:

(array of floats): radial velocity model

Return type:

rv

radvel.orbit.timeperi_to_timetrans(tp, per, ecc, omega, secondary=False)[source]

Convert Time of Periastron to Time of Transit

Parameters:
  • tp (float) – time of periastron
  • per (float) – period [days]
  • ecc (float) – eccentricity
  • omega (float) – argument of peri (radians)
  • secondary (bool) – calculate time of secondary eclipse instead
Returns:

time of inferior conjuntion (time of transit if system is transiting)

Return type:

float

radvel.orbit.timetrans_to_timeperi(tc, per, ecc, omega)[source]

Convert Time of Transit to Time of Periastron Passage

Parameters:
  • tc (float) – time of transit
  • per (float) – period [days]
  • ecc (float) – eccecntricity
  • omega (float) – longitude of periastron (radians)
Returns:

time of periastron passage

Return type:

float

radvel.orbit.true_anomaly(t, tp, per, e)[source]

Calculate the true anomoly for a given time, period, eccentricity.

Parameters:
  • t (array) – array of times in JD
  • tp (float) – time of periastron, same units as t
  • per (float) – orbital period in days
  • e (float) – eccentricity
Returns:

true anomoly at each time

Return type:

array