fastrvm 0.1.1

Relevance Vector Machine in Python with a C++ Core

fastrvm

A fast and clean implementation of the Relevance Vector Machine (RVM).

fastrvm implements Tipping's "sparse Bayesian learning" algorithm [2] in a high-performance C++ core and exposes scikit-learn-compatible Python wrappers for:

• RVR — relevance vector regression
• RVC — relevance vector classification

Key benefits

• Fast training and prediction due to the greedy learning algorithm and a tuned C++ linear-algebra core (Armadillo + Einsmallen for optimization).
• Sparse models that automatically select a small set of relevance vectors.
• scikit-learn-compatible Python wrappers: plug into pipelines, grid search, and common tooling.

Quick Start

Install the latest release from PyPI (wheels are provided for Ubuntu and macOS, Windows requires building from source):

pip install fastrvm

Regression example (RVR):

from fastrvm import RVR
from sklearn.datasets import make_regression
from sklearn.model_selection import train_test_split
from sklearn.metrics import r2_score

X, y = make_regression(n_samples=500, n_features=50, noise=0.1, random_state=0)
X_train, X_test, y_train, y_test = train_test_split(X, y, random_state=0)

model = RVR(kernel='linear', fit_intercept=True, max_iter=2000)
model.fit(X_train, y_train)
print('R2:', r2_score(y_test, model.predict(X_test)))

Classification example (RVC)

from fastrvm import RVC
from sklearn.datasets import make_classification
from sklearn.pipeline import make_pipeline
from sklearn.preprocessing import StandardScaler
from sklearn.model_selection import cross_val_score

X, y = make_classification(n_samples=300, n_features=50, n_informative=10, random_state=0)
clf = make_pipeline(StandardScaler(), RVC(kernel='rbf', gamma='scale', n_jobs=-1))
scores = cross_val_score(clf, X, y, cv=5, scoring='accuracy')
print('5-fold accuracy:', scores.mean())

Notes on the Python API

• Classes: RVR and RVC available from fastrvm.
• Estimator API: implements scikit-learn conventions (fit, predict, etc.).
• Kernel options: rbf, linear, poly, precomputed (scikit-learn-style names). Various kernel hyperparameters such as gamma, degree, and coef0 are supported.
• Multiclass classification: For efficiency reasons RVC uses a one-vs-rest classifier for multiclass classification.

See docs/fastrvm.md for a short reference doc.

Installation from Source

For development install from source:

git clone https://github.com/brdav/fastrvm.git
cd fastrvm
git submodule update --init --recursive
python -m pip install -e '.[dev]'

Minimum build dependencies

• CMake >= 3.18
• Python >= 3.9 (development headers)
• C++17-capable compiler (clang, gcc, or MSVC)
• BLAS/LAPACK implementation (OpenBLAS, MKL, or Accelerate)

Note: Builds on Windows are untested in CI. You can attempt a Windows build but expect manual steps.

The C++ core (sparse Bayesian learning algorithm) can also be built independently:

cmake -S src/cpp -B build/cpp -DCMAKE_BUILD_TYPE=Release
cmake --build build/cpp --target sparsebayes -j

Citation

Key references:

1. Tipping, M. E. (2001). Sparse Bayesian Learning and the Relevance Vector Machine. Journal of Machine Learning Research, 1, 211–244.

2. Tipping, M. E. & Faul, A. C. (2003). Fast Marginal Likelihood Maximisation for Sparse Bayesian Models. Proceedings of the 4th International Workshop on Artificial Intelligence and Statistics (AISTATS / PMLR), pages 276–283, 2003.

This implementation follows the ideas and practical choices from the SparseBayes (v2.0) MATLAB package by Michael Tipping — see the SparseBayes v2.0 download page. Please cite [1] for the core algorithm and [2] for the marginal-likelihood acceleration where applicable.

License

MIT — see LICENSE for details.

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Questions, feature requests, or issues? Open an issue on GitHub.