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funcharts

INFRA · APIS
Velocity0.0

Functional Control Charts

One paper, one release: the functional control chart package ships methods as they get published.

functional-datacontrol-chartsstatistical-process-controlr-packagerobust-statisticsacademic-software
Current state
funcharts implements control charts for functional data — statistical process control where each observation is a curve rather than a number. Its release cadence maps one-to-one onto its authors' publication record: 1.4.0 delivered the robust multivariate framework from Capezza et al. (2022), 1.7.0 the adaptive chart from Centofanti et al. (2025) as it was accepted at Technometrics. Each release adds Phase I and Phase II functions for one named method.
Where it's heading
The early releases were about the package as software — vectorised tensor products, precomputed B-spline inner products, faster cross-validation — and about removing assumptions, most consequentially the assumption that functional data is represented in a B-spline basis. Since 1.4.0 the software work has stopped and the package has become a delivery vehicle for the research group's methods. Robustness came first, adaptivity second, both arriving with the paper rather than ahead of it.
Prediction
The next release will most likely implement whatever this group publishes next, following the same Phase I / Phase II function pairing; nothing in the feed suggests infrastructure work resuming.

Recent moves

  1. 1y ago

    Adaptive multivariate functional control chart added

    Adds the Adaptive Multivariate Functional Control Chart as a Phase I / Phase II function pair, published alongside the Technometrics paper that defines it. Another method in the catalogue, delivered in the package's established shape rather than changing it.

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  2. 2y ago

    Robust multivariate framework: filtering, imputation, and both phases

    The robust multivariate framework arrives as five functions covering the whole pipeline — robust functional PCA, a filtering step, imputation of missing functional data, and the two monitoring phases. Broader than a single chart, but still one published framework transcribed into the package's existing structure.

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  3. 3y ago

    All fda basis systems accepted, not just B-splines

    ⚡ SPARK

    The release that removed the package's built-in assumption about how curves are represented, and tidied its function naming at the same time. Everything since has been method delivery on top of this more general foundation.

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  4. 3y ago

    Vectorised inner products and cross-validation, seed argument dropped

    A performance and ergonomics release: the tensor product in fof_pc() is vectorised, inner products use precomputed B-spline values, and scalar-on-function cross-validation drops its loop. The seed argument is deprecated across the package in favour of ordinary set.seed(), and sim_funcharts() reduces simulation setup to three sample sizes.

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