Toy_HOD_Model¶

class halotools.halo_occupation.Toy_HOD_Model(mass_mask=[12, 13, 14], toy_ncen=[0.1, 0.1, 0.1], toy_nsat=[0.1, 0.1, 0.1], binsize=0.1, threshold=None)[source] [edit on github]¶

Bases: halotools.halo_occupation.HOD_Model

Subclass of HOD_Model object, allowing for explicit specification of the occupation statistics.

Parameters:

mass_mask : array_like, optional.

List the values of $log_{10}M$ of halos occupied by galaxies.

toy_ncen : array_like, optional.

List the desired mean abundance of centrals at the input mass_mask

toy_nsat : array_like, optional.

List the desired mean abundance of satellites at the input mass_mask

Notes

Primarily useful for two reasons. First, constructing weird, unphysical HODs is useful for developing a rigorous test suite, since tests that pass extreme cases will pass reasonable cases. Second, useful to zero in on assembly bias effects that are operative only over specific mass ranges.

Attributes Summary

primary_halo_property_key Model is based on $M = M_{vir}$ .

Methods Summary

`impose_binsize_constraints`(mass_mask, binsize)	Make sure that the user-supplied mask_mask does not result in overlapping mass bins.
`mean_concentration`(logM, halo_type)	Concentration-mass relation of the model.
`mean_ncen`(logM, halo_type)	Expected number of central galaxies in a halo of mass logM.
`mean_nsat`(logM, halo_type)	Expected number of satellite galaxies in a halo of mass logM.

Attributes Documentation

primary_halo_property_key¶: Model is based on $M = M_{vir}$ .

Methods Documentation

impose_binsize_constraints(mass_mask, binsize)[source] [edit on github]¶: Make sure that the user-supplied mask_mask does not result in overlapping mass bins.

mean_concentration(logM, halo_type)[source] [edit on github]¶

Concentration-mass relation of the model.

Parameters:

logM : array_like

array of $log_{10}(M)$ of halos in catalog

halo_type : array

array of halo types. Entirely ignored in this model. Included as a passed variable purely for consistency between the way this function is called by different models.

Returns:

concentrations : array_like

Mean concentration of halos of the input mass, using anatoly_concentration model.

mean_ncen(logM, halo_type)[source] [edit on github]¶

Expected number of central galaxies in a halo of mass logM. For any input logM in the range of mass_mask[ii]-binsize/2 < logM < mass_mask[ii] + binsize/2 for some ii, set $\langle N_{cen} \rangle$ equal to the input toy_ncen[ii].

Parameters:

logM : array

array of $log_{10}(M)$ of halos in catalog

halo_type : array

array of halo types. Entirely ignored in this model.

Returns:

mean_ncen : array

array giving $\langle N_{cen} \rangle$

mean_nsat(logM, halo_type)[source] [edit on github]¶

Expected number of satellite galaxies in a halo of mass logM. For any input logM in the range of mass_mask[ii]-binsize/2 < logM < mass_mask[ii] + binsize/2 for some ii, set $\langle N_{sat} \rangle$ equal to the input toy_nsat[ii].

Parameters:

logM : array

array of $log_{10}(M)$ of halos in catalog

halo_type : array

array of halo types. Entirely ignored in this model.

Returns:

mean_nsat : array

array giving $\langle N_{sat} \rangle$

Navigation

Toy_HOD_Model¶

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