GenMFGrowth

class hmf.cosmology.growth_factor.GenMFGrowth(cosmo: FLRW, **model_parameters)

Port of growth factor routines found in the genmf code.

Parameters:

• cosmo (astropy.cosmology.FLRW instance) – Cosmological model.

• **model_parameters (unpack-dict) –

  Parameters specific to this model. In this case, available parameters are as follows.To see their default values, check the _defaults class attribute.

  dz:

  Step-size for redshift integration

  zmax:

  Maximum redshift to integrate to. Only used for growth_factor_fn().

Attributes

Methods

__init__(cosmo: FLRW, **model_parameters)

dlne_dlna(z)

Compute the derivative of ln(E(a)) with respect to ln(a).

This is useful for the growth factor, which has terms \(E'(a)/E(a) \equiv (1/a)*dlnE/dlna\) in its definition.

This implementation simply uses the exact definition from astropy of E(a) and writes down the derivative analytically.

classmethod get_models() → dict[str, type]

Get a dictionary of all implemented models for this component.

growth_factor(z)

Compute the normalized growth factor, \(D(a) = D^+(a)/D^+(a=1)\).

Parameters:

z (array_like) – Redshift.

Returns:

gf – The growth factor at z.

Return type:

array_like

growth_rate(z) → float | ndarray

Compute the growth rate, \(f(a) = d\ln D^+ / d\ln a\).

Parameters:

z (array_like) – Redshift.

Returns:

gr – The growth rate at z.

Return type:

array_like

radiation_density(z)

The fractional radiation density as a function of redshift.