py21cmfast.wrapper.classy_interface

Module for computing quantities with CLASS.

Attributes

classy_params_default
k_pivot
k_transfer

Classes

EHTransferFunction

Initialize EH transfer function.

Functions

compute_rms(classy_output[, kind, redshifts, ...])	Compute the root-mean-square of a field at given redshifts.
find_redshift_kinematic_decoupling(classy_output)	Find the redshift of kinematic decoupling.
get_transfer_function(classy_output[, kind, z])	Get the transfer function of a field at a given redshift.
run_classy(**kwargs)	Run CLASS with specified input parameters.

Module Contents

py21cmfast.wrapper.classy_interface.compute_rms(classy_output, kind='d_m', redshifts=0, smoothing_radius=0)

Compute the root-mean-square of a field at given redshifts.

Parameters:

• classy_output (classy.Class) – An object containing all the information from the CLASS calculation.

• kind (str, optioanl) – The type of field for which the rms shall be computed. Options are:

  • “d_b”, “d_cdm”, “d_m”: density field of baryons, cold dark matter, or all matter (including massive neutrinos).

  • “v_b”, “v_cdm”: magnitude of the velocity vector field of baryons or CDM (this is gauge dependent).

  • “v_cb”: magnitude of the relative velocity vector field between baryons and CDM (this is gauge independent).

  Default is “d_m”.

• redshifts (np.array or a float, optional) – The redshifts at which the rms shall be computed. Default is 0.

• smoothing_radius (float, optional) – If non-zero, the field will be smoothed with a top hat filter (in real space) with comoving radius that is set to R_smooth. Can also be passed as type ‘astropy.units.quantity.Quantity’ with length unit. Default is 0.

Returns:

rms (np.array) – Array of the rms of the desired field at the given redshifts.

Parameters:

• classy_output (classy.Class)

• kind (str)

• redshifts (collections.abc.Sequence[float])

• smoothing_radius (float)

Return type:

collections.abc.Sequence[float]

py21cmfast.wrapper.classy_interface.find_redshift_kinematic_decoupling(classy_output)

Find the redshift of kinematic decoupling.

For simplicity, we approximate the redshift of kinematic decoupling to be the same redshift of recombination, which is defined as the moment when x_e = n_e/(n_H + n_He) = 0.1. For LCDM with Planck 2018 parameters, this corresponds to z_dec ~ 1070.

Parameters:

classy_output (classy.Class) – An object containing all the information from the CLASS calculation.

Returns:

z_dec (float) – Redshift of kinematic decoupling.

Parameters:

classy_output (classy.Class)

Return type:

float

py21cmfast.wrapper.classy_interface.get_transfer_function(classy_output, kind='d_m', z=0)

Get the transfer function of a field at a given redshift.

Parameters:

• classy_output (classy.Class) – An object containing all the information from the CLASS calculation.

• kind (str, optioanl) – The type of field for which the rms shall be computed. Options are: * “d_b”, “d_cdm”, “d_m”: density field of baryons, cold dark matter, or all matter (including massive neutrinos). * “v_b”, “v_cdm”: magnitude of the velocity vector field of baryons or CDM (this is gauge dependent). * “v_cb”: magnitude of the relative velocity vector field between baryons and CDM (this is gauge independent). Default is “d_m”.

• z (float, optional) – The redshift at which the transfer function shall be computed. Default is 0.

Returns:

transfer (np.array) – Array of the desired transfer function at the given redshift.

Parameters:

• classy_output (classy.Class)

• kind (str)

• z (float)

Return type:

collections.abc.Sequence[float]

py21cmfast.wrapper.classy_interface.run_classy(**kwargs)

Run CLASS with specified input parameters.

Parameters:

kwargs – Optional keywords to pass to CLASS.

Returns:

output (classy.Class) – An object containing all the information from the CLASS calculation.

Return type:

classy.Class

py21cmfast.wrapper.classy_interface.classy_params_default

py21cmfast.wrapper.classy_interface.k_pivot

py21cmfast.wrapper.classy_interface.k_transfer