code: def get_conv_params(mass1, mass2, spin1z, spin2z, metricParams, fUpper,
                      lambda1=None, lambda2=None, quadparam1=None,
                      quadparam2=None):
      
  
      # Do this by masses -> lambdas
      lambdas = get_chirp_params(mass1, mass2, spin1z, spin2z,
                                 metricParams.f0, metricParams.pnOrder,
                                 lambda1=lambda1, lambda2=lambda2,
                                 quadparam1=quadparam1, quadparam2=quadparam2)
      # and lambdas -> mus
      mus = get_mu_params(lambdas, metricParams, fUpper)
      return mus
docs: Function to convert between masses and spins and locations in the mu
      parameter space. Mu = Cartesian metric, but not principal components.
  
      Parameters
      -----------
      mass1 : float
          Mass of heavier body.
      mass2 : float
          Mass of lighter body.
      spin1z : float
          Spin of body 1.
      spin2z : float
          Spin of body 2.
      metricParams : metricParameters instance
          Structure holding all the options for construction of the metric
          and the eigenvalues, eigenvectors and covariance matrix
          needed to manipulate the space.
      fUpper : float
          The value of fUpper to use when getting the mu coordinates from the
          lambda coordinates. This must be a key in metricParams.evals and
          metricParams.evecs (ie. we must know how to do the transformation for
          the given value of fUpper)
  
      Returns
      --------
      mus : list of floats or numpy.arrays
          Position of the system(s) in the mu coordinate system