plskit (Python)

Python wrapper for plskit — Partial Least Squares with modern inference (canonical percentile CIs, split_exact, split_nb), backed by a Rust engine.

Part of the plskit project — the Rust core, sibling wrappers (R and Julia, planned), shared test corpus, issues, and PRs all live there.

Install

pip install plskit

Wheels are built for Linux, macOS, and Windows on recent Python versions (>=3.10). When a wheel is unavailable for your platform, pip falls back to building from the source distribution, which requires a working Rust toolchain.

A 60-second look

import numpy as np
import plskit

X = np.random.default_rng(0).normal(size=(200, 20))
y = X[:, :3].sum(axis=1) + np.random.default_rng(1).normal(size=200)

# Fit at fixed K, or let plskit pick K via cross-validation.
model   = plskit.pls1_fit(X, y, k=3, seed=42)
optimal = plskit.pls1_fit(X, y, k="optimal", k_max=10, seed=42)

y_hat = plskit.pls1_predict(model, X_new=X[:5])

# Confirmatory test at the pre-specified K.
sig = plskit.pls1_confirmatory_test(
    X, y, k=3,
    method="split_nb", args={"n_splits": 50}, seed=42,
)
print(sig.pvalue, sig.statistic)

PLS1 (single continuous y) is the only family available in v0.1; PLS2, PLS3 / PLSSVD, and multi-block follow.

Public surface

Functions: preprocess, pls1_fit, pls1_predict, pls1_confirmatory_test, pls1_find_k_optimal, pls1_find_k_sequence, pls1_perm_null, pls1_rotation_stability, rotate.

Result types: PreprocessResult, PLS1Result, ConfirmatoryTestResult, FindKOptimalResult, FindKSequenceResult, PermNullResult, RotationStabilityResult, RotateResult, RotationSpec, CIScalar, ConfirmatoryCI. All are frozen dataclasses and carry the inputs and seed that produced them.

Errors raised by the Rust engine surface as plskit.PlsKitError (with PlsKitInvalidWeights and PlsKitResamplingDegenerate subclasses) and carry a stable .code for programmatic handling.

This is a thin wrapper

All numerical work runs inside the plskit Rust crate. The Python package converts inputs to f64, calls the engine, and wraps the result. Bug reports and feature requests belong on the monorepo issue tracker.

Citation

Lenartowicz, P., Plisiecki, H. (2026). Cheap Per-Component Testing for PLS, Stable Under Rotation (Under Review).

License

GPL-3.0-or-later.