roman_photoz

The roman_photoz package provides tools for processing multiband catalogs produced by the Roman Space Telescope Calibration Pipeline (romancal) to estimate photometric redshifts.

Overview

The Roman Space Telescope will produce large catalogs of astronomical objects. This package provides utilities for:

  • Processing Roman catalog data in parquet and ASDF formats;

  • Translating filter definitions into the format expected by LePhare;

  • Generating simulated images and catalogs for development and testing;

  • Estimating photometric redshifts using rail/LePhare.

Getting Started

Developer Guide

Modules

API Reference

class roman_photoz.RomanCatalogHandler(catname: str = '', fit_colname: str = 'segment_{}_flux', fit_err_colname: str = 'segment_{}_flux_err')

Bases: object

A class to handle Roman catalog operations including reading and formatting it in a suitable way for roman_photoz.

process(input_filename: str | None = None) → ndarray

Process the catalog by reading and formatting it.

Returns:

The formatted catalog.

Return type:

np.ndarray

class roman_photoz.RomanCatalogProcess(config_filename: dict | str = '', model_filename: str = 'roman_model.pkl')

Bases: object

A class to process a Roman Telescope multiband catalog data using rail and lephare.

data

Dictionary to store the processed data.

Type:

dict

flux_cols

List of flux column names.

Type:

list

flux_err_cols

List of flux error column names.

Type:

list

inform_stage

Informer stage for creating the library of SEDs.

Type:

RailStage

estimated

Estimator stage for finding the best fits from the library.

Type:

RailStage

model_filename

Name of the pickle model file to use.

Type:

str

property informer_model_exists

Check if the informer model file exists.

Returns:

True if the model file exists, False otherwise.

Return type:

bool

property informer_model_path

Get the path to the informer model file used.

The path is determined by checking the INFORMER_MODEL_PATH environment variable first, falling back to LEPHAREWORK if not set.

Returns:

The path to the informer model file.

Return type:

str

process(input_filename, output_filename: str | None = None, output_format: str = 'parquet', fit_colname: str = 'segment_{}_flux', fit_err_colname: str = 'segment_{}_flux_err')

Process the Roman catalog data.

Parameters:

  • input_filename (str) – Name of the input file.

  • output_filename (str, optional) – Name of the output file. If none is provided (default), the input file will be updated in place.

  • output_format (str, optional) – Format to save the results. Supported formats are “parquet” (default) and “asdf.”

  • flux_type (str, optional) – The type of flux to use for fitting. Options are “psf” (default), “kron”, “segment”, or “aperture.”

class roman_photoz.SimulatedCatalog(nobj: int = 1000, mag_noise: float = 0.1, seed=None)

Bases: object

A class to create a simulated catalog using the Roman telescope data.

data

A dictionary to store the data.

Type:

OrderedDict

lephare_config

Configuration for LePhare.

Type:

dict

flux_cols

List of flux column names.

Type:

list

flux_err_cols

List of flux error column names.

Type:

list

inform_stage

Placeholder for inform stage.

Type:

None

estimated

Holds all the results from roman_photoz.

Type:

None

filter_lib

Placeholder for filter library.

Type:

None

simulated_data_filename

Filename for the simulated data.

Type:

str

simulated_data

Placeholder for simulated data.

Type:

None

process(output_path: str = '', output_filename: str = 'roman_simulated_catalog.parquet', return_catalog: bool = False, refresh_lib_mag: bool = False)

Run the process to create the simulated catalog.

Parameters:

  • output_path (str, optional) – Path to save the output catalog (default: “”).

  • output_filename (str, optional) – Filename for the output catalog.

  • return_catalog (bool, optional) – If True, return the catalog in memory instead of saving to file. Default is False to maintain backward compatibility.

Returns:

The simulated catalog if return_catalog is True, otherwise None.

Return type:

Table or None

roman_photoz.setup_logging(level=20, log_file='roman_photoz.log')

Set up logging configuration for roman_photoz module

Indices and tables