sage_analysis.sage_binary

This module defines the SageBinaryData class. This class interfaces with the Model class to read in binary data written by SAGE. The value of sage_output_format is generally sage_binary if it is to be read with this class.

If you wish to ingest data from your own flavour of SAGE, please open a Github issue, I plan to add this documentation in future :)

Author: Jacob Seiler.

class sage_analysis.sage_binary.SageBinaryData(model: sage_analysis.model.Model, sage_file_to_read: str)

Class intended to inteface with the Model class to ingest the data written by SAGE. It includes methods for reading the output galaxies, setting cosmology etc. It is specifically written for when sage_output_format is sage_binary.

__init__(model: sage_analysis.model.Model, sage_file_to_read: str) → None

Instantiates the Data Class for reading in SAGE binary data. In particular, generates the numpy structured array to read the output galaxies.

model: Model instance

The model that this data class is associated with; this class will read the data for this model.

close_file(model: sage_analysis.model.Model)

An empty method to ensure consistency with the HDF5 data class. This is empty because snapshots are saved over different files by default in the binary format.

determine_num_gals(model: sage_analysis.model.Model, *args)

Determines the number of galaxies in all files for this Model.

Parameters:

• model (Model class) – The Model we’re reading data for.
• *args (Any) – Extra arguments to allow other data class to pass extra arguments to their version of determine_num_gals.

determine_volume_analyzed(model: sage_analysis.model.Model) → float

Determines the volume analyzed. This can be smaller than the total simulation box.

Parameters:model (Model instance) – The model that this data class is associated with. Returns:volume – The numeric volume being processed during this run of the code in (Mpc/h)^3. Return type:float

read_gals(model: sage_analysis.model.Model, file_num: int, snapshot: int, pbar: Optional[tqdm.std.tqdm] = None, plot_galaxies: bool = False, debug: bool = False)

Reads the galaxies of a model file at snapshot specified by snapshot.

Parameters:

• model (Model class) – The Model we’re reading data for.
• file_num (int) – Suffix number of the file we’re reading.
• pbar (tqdm class instance, optional) – Bar showing the progress of galaxy reading. If None, progress bar will not show.
• plot_galaxies (bool, optional) – If set, plots and saves the 3D distribution of galaxies for this file.
• debug (bool, optional) – If set, prints out extra useful debug information.

Returns:

gals – The galaxies for this file.

Return type:

numpy structured array with format given by :py:method:`~_get_galaxy_struct`

Notes

tqdm does not play nicely with printing to stdout. Hence we disable the tqdm progress bar if debug=True.

read_sage_params(sage_file_path: str) → Dict[str, Any]

Read the SAGE parameter file.

Parameters:sage_file_path (string) – Path to the SAGE parameter file. Returns:model_dict – Dictionary containing the parameter names and their values. Return type:dict [str, var]

update_snapshot_and_data_path(model: sage_analysis.model.Model, snapshot: int, use_absolute_path: bool = False)

Updates the _sage_data_path to point to a new redshift file. Uses the redshift array redshifts.

Parameters:

• snapshot (int) – Snapshot we’re updating _sage_data_path to point to.
• use_absolute_path (bool) – If specified, will use the absolute path to the SAGE output data. Otherwise, will use the path that is relative to the SAGE parameter file. This is hand because the SAGE parameter file can contain either relative or absolute paths.