# Priors¶

class radvel.prior.EccentricityPrior(num_planets, upperlims=0.99)[source]

Physical eccentricities

Prior to keep eccentricity between 0 and a specified upper limit.

Parameters: num_planets (int or list) – Planets to apply the eccentricity prior. If an integer is given then all planets with indexes up to and including the specified integer will be included in the prior. If a list is given then the prior will only be applied to the specified planets. upperlims (float or list of floats) – List of eccentricity upper limits to assign to each of the planets. If a float is given then all planets must have eccentricities less then this value. If a list of floats is given then each planet can have a different eccentricity upper limit.
class radvel.prior.Gaussian(param, mu, sigma)[source]

Gaussian prior

Guassian prior on a given parameter.

Parameters: param (string) – parameter label mu (float) – center of Gaussian prior sigma (float) – width of Gaussian prior
class radvel.prior.HardBounds(param, minval, maxval)[source]

Prior for hard boundaries

This prior allows for hard boundaries to be established for a given parameter.

Parameters: param (string) – parameter label minval (float) – minimum allowed value maxval (float) – maximum allowed value
class radvel.prior.PositiveKPrior(num_planets)[source]

K must be positive

A prior to prevent K going negative. Be careful with this as it can introduce a bias to larger K values.

Parameters: num_planets (int) – Number of planets. Used to ensure K for each planet is positive
class radvel.prior.SecondaryEclipsePrior(planet_num, ts, ts_err)[source]

Secondary eclipse prior

Implied prior on eccentricity and omega by specifying measured secondary eclipse time

Parameters: planet_num (int) – Number of planet with measured secondary eclipse ts (float) – Secondary eclipse midpoint time. Should be in the same units as the timestamps of your data. ts_err (float) – Uncertainty on secondary eclipse time