hearin15_model_dictionary¶
- halotools.empirical_models.hearin15_model_dictionary(central_assembias_strength=1, central_assembias_strength_abscissa=[1000000000000.0], satellite_assembias_strength=0.2, satellite_assembias_strength_abscissa=[1000000000000.0], **kwargs)[source]¶
Dictionary to build an HOD-style model in which central and satellite occupations statistics are assembly-biased.
See Hearin et al. (2015) Composite Model for a tutorial on this model.
- Parameters:
- thresholdfloat, optional
Stellar mass threshold of the mock galaxy sample. Default value is specified in the
model_defaults
module.- redshiftfloat, optional
Default is set in the
sim_defaults
module.- sec_haloprop_keystring, optional
String giving the column name of the secondary halo property modulating the occupation statistics of the galaxies. Default value is specified in the
model_defaults
module.- central_assembias_strengthfloat or list, optional
Fraction or list of fractions between -1 and 1 defining the assembly bias correlation strength. Default is a constant strength of 0.5.
- central_assembias_strength_abscissalist, optional
Values of the primary halo property at which the assembly bias strength is specified. Default is a constant strength of 0.5.
- satellite_assembias_strengthfloat or list, optional
Fraction or list of fractions between -1 and 1 defining the assembly bias correlation strength. Default is a constant strength of 0.5.
- satellite_assembias_strength_abscissalist, optional
Values of the primary halo property at which the assembly bias strength is specified. Default is a constant strength of 0.5.
- splitfloat, optional
Fraction between 0 and 1 defining how we split halos into two groupings based on their conditional secondary percentiles. Default is 0.5 for a constant 50/50 split.
- concentration_binningtuple, optional
Three-element tuple. The first entry will be the minimum value of the concentration in the lookup table for the satellite NFW profile, the second entry the maximum, the third entry the linear spacing of the grid. Default is set in
model_defaults
. If high-precision is not required, the lookup tables will build much faster ifconcentration_binning
is set to (1, 25, 0.5).
Examples
>>> model_dictionary = hearin15_model_dictionary() >>> model_instance = factories.HodModelFactory(**model_dictionary)
The default settings are set in the
model_defaults
module. To load a model based on a different threshold and redshift:>>> model_dictionary = hearin15_model_dictionary(threshold = 11, redshift = 1) >>> model_instance = factories.HodModelFactory(**model_dictionary)
For this model, you can also use the following syntax candy, which accomplishes the same task as the above:
>>> model_instance = factories.PrebuiltHodModelFactory('hearin15', threshold = 11, redshift = 1)
As with all instances of the
PrebuiltHodModelFactory
, you can populate a mock by passing the model a halo catalog:>>> from halotools.sim_manager import FakeSim >>> halocat = FakeSim(redshift = model_instance.redshift) >>> model_instance.populate_mock(halocat)