synthpop.modules.metallicity.double_gaussian
============================================

.. py:module:: synthpop.modules.metallicity.double_gaussian

.. autoapi-nested-parse::

   Metallicity class for a double Gaussian distribution, where the two
   distributions have a relative weight, upper and lower limits,
   and each Gaussian is given a mean and standard deviation.



Classes
-------

.. autoapisummary::

   synthpop.modules.metallicity.double_gaussian.DoubleGaussian


Module Contents
---------------

.. py:class:: DoubleGaussian(weight: float, mean1: float, std1: float, mean2: float, std2: float, low_bound: float = -4, high_bound: float = 0.5, **kwargs)

   Bases: :py:obj:`synthpop.modules.metallicity._metallicity.Metallicity`


   Double Gaussian metallicity class

   Attributes
   ----------
   metallicity_func_name : string
       A class attribute for the name of the _MetallicityBase subclass that this is.
   weight  : float
       percentage of stars belonging to the first Gaussian distribution ( A1/(A1+A2))
   mean1 : float [[Fe/H]]
       the mean value of the first Gaussian distribution
   std1 : float [[Fe/H]]
       the standard deviation of the first Gaussian distribution
   mean2 : float [[Fe/H]]
       the mean value of the second Gaussian distribution
   std2 : float [[Fe/H]]
       the standard deviation of the second Gaussian distribution
   lower_bound : float [[FE/H]]
       lower limit for truncation of the distribution
   upper_bound : float [[FE/H]] 
       upper limit for truncation of the distribution

   Methods
   -------
   __init__(self,Population) : None
       check that required attributes of Population are present:
           -Population.metallicity_func_kwargs : float
   random_metallicity(self) : float
       return a random metallicity drawn from the weighted double Gaussian
   average_metallicity(self) : float
       return the average metallicity


   .. py:attribute:: metallicity_func_name
      :value: 'double-gaussian'



   .. py:attribute:: weight


   .. py:attribute:: mean1


   .. py:attribute:: std1


   .. py:attribute:: mean2


   .. py:attribute:: std2


   .. py:attribute:: lower
      :value: -4



   .. py:attribute:: upper
      :value: 0.5



   .. py:method:: _gen_met(N: int = 1) -> numpy.ndarray

      generate random metallicities using a mixture methode



   .. py:method:: draw_random_metallicity(N: int or None = None, **kwargs) -> np.ndarray or float

      Returns one or more metallicities in [Fe/H] from a double Gaussian distribution.

      Parameters
      ----------
      N : int, None, optional
          if N is set to an integer, an array with N random ages is returned

      Returns
      -------
      val : ndarray, float [Gyr]
          single metallicities or ndarray of N metallicities in [Fe/H]



   .. py:method:: average_metallicity() -> float

      Determine the average metallicity of the population



   .. py:method:: likelyhood_distribution(met: numpy.ndarray) -> numpy.ndarray

      analytic version  of likelyhood_distribution. only used for the validating