The RV Model

class radvel.model.Parameter(value=None, vary=True, mcmcscale=None)[source]

Object to store attributes of each orbital parameter


float – value of parameter.


Bool – True if parameter is allowed to vary in MCMC fits, false if fixed.


float – step size to be used for MCMC fitting

class radvel.model.Parameters(num_planets, basis='per tc secosw sesinw logk', planet_letters=None)[source]

Object to store the orbital parameters.

Parameters to describe a radial velocity orbit stored as an OrderedDict

  • num_planets (int) – Number of planets in model
  • basis (string) – parameterization of orbital parameters. See radvel.basis.Basis for a list of valid basis strings.
  • planet_letters (Dictionary[optional) – custom map to match the planet numbers in the Parameter object to planet letters. Default {1: ‘b’, 2: ‘c’, etc.}. The keys of this dictionary must all be integers.

radvel.Basis – Basis object


list – orbital parameters contained within the specified basis


int – number of planets in the model


>>> import radvel
# create a Parameters object for a 2-planet system with
# custom planet number to letter mapping
>>> params = radvel.Parameters(2, planet_letters={1:'d', 2:'e'})

Map Parameters keys to pretty TeX code representations.

Parameters:param_list (list) – (optional) Manually pass a list of parameter labels
Returns:dictionary mapping Parameters keys to TeX code
Return type:dict
class radvel.model.RVModel(params, time_base=0)[source]

Generic RV Model

This class defines the methods common to all RV modeling classes. The different RV models, having different parameterizations inherit from this class.