GA Matrix

GA Matrix provides small NumPy-backed matrix containers with label-based access, long-form pandas import/export helpers, and optional timestamp support for origin-destination data.

The PyPI distribution is named ga-matrix; the import package is named matrix.

Installation

python -m pip install ga-matrix

Development and test tools are available as extras:

python -m pip install -e ".[test]"
python -m pip install -e ".[dev]"

Quick Start

from matrix import MatrixOD

rows = ["A", "B"]
cols = ["X", "Y"]

od = MatrixOD(rows, cols, init={"A": {"X": 10}, "B": {"Y": 5}})
od["A", "Y"] = 3

assert od["A", "X"] == 10
assert od.sum() == 18

MatrixOD

MatrixOD stores a 2D origin-destination matrix. Rows and columns can be passed as label sequences or existing label-to-position mappings.

import pandas as pd

from matrix import MatrixOD

df = pd.DataFrame(
    [
        {"origin": "A", "destination": "X", "trips": 10},
        {"origin": "B", "destination": "Y", "trips": 5},
    ]
)

od = MatrixOD.read_df(
    rows=["A", "B"],
    cols=["X", "Y"],
    df=df,
    o_field="origin",
    d_field="destination",
    value_field="trips",
)

roundtrip = od.write_df(o_field="origin", d_field="destination", value_field="trips")

Supported operations are element-wise addition, subtraction, multiplication, and division with either a scalar or another matrix with the same labels.

scaled = od * 1.2
delta = scaled - od
col_totals = od.sum(axis=0)
row_totals = od.sum(axis=1)

MatrixODT

MatrixODT stores one MatrixOD per timestamp.

from matrix import MatrixODT

odt = MatrixODT(
    rows=["A", "B"],
    cols=["X", "Y"],
    timestamps=[0, 1],
    init={
        0: {"A": {"X": 10}},
        1: {"B": {"Y": 5}},
    },
)

assert odt["A", "X", 0] == 10
assert odt["A", "X", 99] == 0
assert odt.sum(axis=2)["A", "X"] == 10

MatrixODT.read_df() accepts a long-form DataFrame with origin, destination, timestamp, and value columns. If timestamps is omitted, timestamp labels are inferred from the DataFrame in first-seen order.

API Summary

• MatrixOD(rows, cols, init=None, copy=False, mode=None)
• MatrixOD.read_df(rows, cols, df, o_field="o", d_field="d", value_field="value")
• MatrixOD.read_csv(rows, cols, file, ...)
• MatrixOD.write_df(...)
• MatrixOD.write_csv(file, ...)
• MatrixODT(rows, cols, timestamps, init=None, copy=False, mode=None)
• MatrixODT.read_df(rows, cols, timestamps=None, df=None, ...)
• MatrixODT.read_csv(rows, cols, file, timestamps=None, ...)
• MatrixODT.write_df(...)
• MatrixODT.write_csv(file, ...)

Development

GA Matrix supports Python 3.10 and newer.

python -m pip install -e ".[dev]"
python -m compileall -q src
python -m pytest --cov=matrix --cov-report=term-missing
ruff check .
mypy
python -m pip check
python -m build
python -m twine check dist/*

Releases

src/matrix/_version.py is the only version source. To publish a release:

1. Update __version__ in _version.py and commit the release changes.
2. Push main and wait for CI to pass.
3. Configure the PyPI Trusted Publisher with project ga-matrix, owner andreagemma, repository matrix, workflow release.yml, and environment pypi.
4. Run the Create release GitHub Actions workflow. With no override it creates the v<version> tag, creates release notes, and dispatches the build and PyPI publication workflow.

PyPI versions are immutable. Increment _version.py before publishing different content.

License

GA Matrix is distributed under the MIT License. See LICENSE.