CosmoFit.CPL¶

class CosmoFit.CPL(params)[source]¶

Bases: Cosmology

Chevallier-Polarski-Linder (CPL) dark-energy model.

Equation of state

w(z) = w0 + wa * z / (1 + z)

__init__(params)¶

Methods

`E`(z)	Dimensionless Hubble parameter.
`H`(z)
`Omega_de`(z)	Dark-energy density parameter.
`Omega_matter`(z)	Matter density at redshift `z`, in units of today's critical density -- i.e. the `Omega_m (1+z)^3` term as it appears inside `E(z)^2`, before dividing by `E(z)^2`.
`__init__`(params)
`background_jumps`()	Redshifts at which this model's `E(z)` is discontinuous.
`dEdz`(z)	Derivative of E(z).
`fde`(z)	Dark-energy density evolution factor.
`matter_exchange`(z)	Rate at which matter gains energy from the dark sector, in units of the expansion rate: `psi = Q / (H rho_m)`, with `rho_m' + 3 rho_m = Q / H` (`' = d/dln a`).
`mu`(a[, k])	Effective-to-Newtonian gravitational coupling ratio, G_eff(a,k)/G_N, entering the linear growth equation solved by `GrowthCalculator` (see that module's docstring for the equation itself).
`plain_name`()	This model's name as plain text: `MODEL_NAME` if it declares one, else the class name.
`plot_label`()	This model's name as it should appear in a figure legend or title -- `MODEL_LABEL` (LaTeX) if it declares one, else `plain_name()`.
`refresh`()	Rebuild internal numerical tables after the underlying `params` object has been mutated in place (e.g. by `params.update(theta)` during an MCMC step).
`w`(z)	Dark-energy equation of state.

Attributes

`A_planck`
`A_s`
`EXTRA_PARAMS`	Extra parameters this model adds beyond CosmologyParameters.
`FLAT_ONLY`	Whether this model is defined for a flat universe only.
`H0`
`MB`
`MODEL_LABEL`	a LaTeX math string where the plain name is really a set of symbols (`LCDM` -> `$\Lambda$CDM`), None where the plain name is already what a reader should see (an acronym like `CPL`).
`MODEL_NAME`	Plain-text name for this model, for tables, JSON and log lines.
`N_eff`
`Omega_b`
`Omega_de0`
`Omega_k`
`Omega_m`
`alpha`
`compute_rd`	Whether `rd` is computed from the physical densities (`rd_computed()`) rather than read from the free `rd` parameter.
`derive_sigma8`	Whether `sigma8` is derived from the Boltzmann code rather than read from the free `sigma8` parameter.
`h`	Reduced Hubble constant, `H0 / 100`.
`ln1e10As`
`m_nu`
`n_s`
`omega_b_h2`	Physical baryon density, `Omega_b h^2` -- the combination BBN and the CMB actually constrain.
`omega_cdm_h2`	Physical cold dark matter density, `Omega_c h^2` -- matter less baryons.
`omega_m_h2`	Physical matter density, `Omega_m h^2`.
`rd`	The sound horizon at the drag epoch [Mpc] that the BAO likelihoods divide by.
`sigma8`	Present-day `sigma_8`, the normalization every growth prediction is built on.
`tau_reio`
`w0`
`wa`