README.md

gladeparser

Parser for the GLADE+ galaxy catalog.

Usage

To read the catalog into a pandas.DataFrame:

from gladeparser import to_pandas_df

filename = "path/to/catalog"
df = to_pandas_df(filename)

The preferred way of reading the catalog is using a polars backend, especially if you want to filter out the data:

from gladeparser import to_polars_df
import polars as pl

# Grab objects from 2MASS catalog with redshifts corrected for peculiar velocity
filters = (
    pl.col("2MASS name").is_not_null(),
    pl.col("z_cmb").is_not_null(),
    pl.col("z_cmb") > 0,
    pl.col("z flag") == 1,
    pl.col("dist flag").is_in([1, 3])
)

# Selected columns
cols = ["ra", "dec", "z_cmb"]

filename = "path/to/catalog"
df = to_polars_df(filename, *filters, cols=cols)

Parsing a subset of columns

from gladeparser import to_pandas_df, get_columns

# Select the columns you want and return their names
# See more options in get_columns docstring
cols = get_columns('Localization', 'Distance', names=True)

filename = "path/to/catalog"
df = to_pandas_df(filename, cols=cols)

Installation

Clone the repo and run

pip install .

Testing

Make sure that you have pytest installed, or run

pip install .[dev]

Then run

pytest

References

See the GLADE+ paper on arXiv.