halotools¶
Welcome to the halotools documentation. Halotools is a python package designed to study large-scale structure, cosmology, and galaxy evolution using N-body simulations and halo models. The code is publicly available at https://github.com/halotools.
The package is still under rapid development, with its API being restructured frequently. In short, it is still not “stable.” In particular, if you download the code and write scripts based on the current API, your scripts will likely not correctly interface with future versions of the code.
Presently, only the basic API is documented. Once more of the core functionality is in place, step-by-step examples will be included, as will iPython notebook tutorials.
Contributions to the halotools package are warmly welcomed! If you are interested in collaborating, and/or would like to know more about the intended scope of the project, please contact Andrew Hearin at andrew-dot-hearin-at-yale-dot-edu.
Reference/API¶
halotools.hod_designer Module¶
The sole purpose of this module is to provide an interface between halotools.hod_components and halotools.hod_factory. halotools.hod_designer creates a set of instructions that is passed to halotools.hod_factory, in the form of a dictionary. The dictionary provides a blueprint telling the factory how to build an HOD model from the HOD components.
Classes¶
| HodModelDesigner(*args, **kwargs) | This class is used to create a blueprint to give to halotools.hod_factory; the HOD factory will use the blueprint to instantiate a composite HOD model; all of the behavior of the composite model derives from a set of component models. |
Class Inheritance Diagram¶
halotools.make_mocks Module¶
This module contains the classes and functions used to populate N-body simulations with realizations of galaxy-halo models. Currently only set up for HOD-style models, but near-term features include CLF/CSMF models, and (conditional) abundance matching models. Class design is built around future MCMC applications.
Functions¶
| enforce_periodicity_of_box(coords, box_length) | Function used to apply periodic boundary conditions of the simulation, so that mock galaxies all lie in the range [0, Lbox]. |
Classes¶
| HOD_mock([simulation_data, simname, ...]) | Class used to build mock realizations of any HOD-style model defined in halo_occupation module. |
Class Inheritance Diagram¶
halotools.halo_occupation Module¶
This module contains the classes and methods used to connect galaxies to halos using HOD-style models.
Functions¶
| cumulative_NFW_PDF(x, c) | Integral of an NFW profile with concentration c. |
| anatoly_concentration(logM) | Power law fitting formula for the concentration-mass relation of Bolshoi host halos at z=0 Taken from Klypin et al. |
| solve_for_polynomial_coefficients(abcissa, ...) | Solves for coefficients of the unique, minimum-degree polynomial that passes through the input abcissa and attains values equal the input ordinates. |
Classes¶
| HOD_Model([parameter_dict, threshold]) | Base class for any HOD-style model of the galaxy-halo connection. |
| Zheng07_HOD_Model([parameter_dict, threshold]) | Subclass of HOD_Model object, where functional forms for occupation statistics are taken from Zheng et al. |
| Leauthaud11_SHMR_Model([parameter_dict, ...]) | Subclass of HOD_Model object, where functional forms for occupation statistics are taken from Leauthaud et al. |
| Toy_HOD_Model([mass_mask, toy_ncen, ...]) | Subclass of HOD_Model object, allowing for explicit specification of the occupation statistics. |
| Assembias_HOD_Model() | Abstract base class for any HOD model with assembly bias. |
| HOD_Quenching_Model() | Abstract base class for models determining mock galaxy quenching. |
| vdB03_Quenching_Model([baseline_hod_model, ...]) | Subclass of HOD_Quenching_Model, providing a traditional HOD model of galaxy quenching, in which quenching designation is purely determined by host halo virial mass. |
| Assembias_HOD_Quenching_Model() | Abstract base class for any HOD model in which both galaxy abundance and galaxy quenching on Mvir plus an additional property. |
| Satcen_Correlation_Polynomial_HOD_Model([...]) | HOD-style model in which satellite abundance is correlated with the presence of a central galaxy. |
| Polynomial_Assembias_HOD_Model([...]) | Concrete subclass of Assembias_HOD_Model in which occupation statistics exhibit assembly bias, where some secondary host halo property modulates the mean galaxy abundance. |
| Polynomial_Assembias_HOD_Quenching_Model([...]) | Concrete subclass of Assembias_HOD_Model. |
Class Inheritance Diagram¶
halotools.occupation_helpers Module¶
This module contains general purpose helper functions used by many of the hod model components.
Functions¶
| solve_for_polynomial_coefficients(abcissa, ...) | Solves for coefficients of the unique, minimum-degree polynomial that passes through the input abcissa and attains values equal the input ordinates. |
| format_parameter_keys(input_parameter_dict, ...) | Simple method that tests whether the input keys are correct, and if so, appends the key names with the galaxy type that they pertain to. |
halotools.mock_factory Module¶
Module used to construct mock galaxy populations. Each mock factory only has knowledge of a simulation snapshot and composite model object. Currently only composite HOD models are supported.
Classes¶
| HodMockFactory(snapshot, composite_model[, ...]) | The constructor of this class takes a snapshot and a composite model as input, and returns a Monte Carlo realization of the composite model painted onto the input snapshot. |
Class Inheritance Diagram¶
halotools.hod_factory Module¶
Module containing the primary class used to build composite HOD models from a set of components.
Class Inheritance Diagram¶
halotools.hod_components Module¶
This module contains functions and classes providing mappings between halos and the abundance and properties of galaxies residing in those halos. The classes serve primarily as components used by halotools.hod_factory and halotools.hod_designer, which act together to compose the behavior of the components into composite models.
Classes¶
| Kravtsov04Cens([parameter_dict, threshold, ...]) | Erf function model for the occupation statistics of central galaxies, introduced in Kravtsov et al. |
| Kravtsov04Sats([parameter_dict, threshold, ...]) | Power law model for the occupation statistics of satellite galaxies, introduced in Kravtsov et al. |
| vdB03Quiescence(gal_type[, parameter_dict, ...]) | Traditional HOD-style model of galaxy quenching in which the expectation value for a binary SFR designation of the galaxy is purely determined by the primary halo property. |
Class Inheritance Diagram¶
halotools.jeans Module¶
Module encoding jeans analysis for spherically symmetric halos with spherically symmetric distributions of tracer particles.
Author: Surhud More (surhudkicp@gmail.com), Kavli IPMU
Bugs: Report to the above email address
halotools.defaults Module¶
Module expressing various default values of halotools.
All hard-coding should be restricted to this module, whenever possible.
halotools.read_nbody Module¶
Methods and classes to load halo and particle catalogs into memory.
Classes¶
| processed_snapshot([simname, scale_factor, ...]) | Class containing halo and particle data taken from a single snapshot of some Nbody simulation. |
| Catalog_Manager() | Container class for managing I/O of halo & particle catalogs. |
Class Inheritance Diagram¶
