.. _auto_curve_savitsky_golay_smooth:

*SAVTISKY GOLAY FILTER*
=======================

Applies a Savitzky-Golay smoothing filter to an input curve using a locally weighted polynomial fit. Use this worker to reduce noise in time-history or signal curves while preserving peak shape and derivatives better than simple moving-average filters.

When to use
-----------

Classification: **process**.

Tagged: ``curve``, ``filter``, ``lowess``, ``noise-reduction``, ``polynomial-fit``, ``savitzky-golay``, ``signal``, ``smoothing``.

Inputs
------

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   * - Label
     - ID
     - Type
     - Default
     - Required
     - Description
   * - Curve In
     - curve_in
     - vector
     - —
     - 
     - Input curve (x/y vector) to be smoothed; accepts any time-history or signal curve in d3VIEW vector format.
   * - Percentage Of Points
     - percentageof_points
     - scalar
     - 1
     - 
     - Fraction of the total number of curve points used as the local smoothing window, expressed as a percentage (1–100); larger values produce heavier smoothing — default is 1 (1%).
   * - Weight Type
     - weight_type
     - scalar
     - 1
     - 
     - Weighting kernel applied within each local window: 'tri-cube' (default, recommended for most signals) gives stronger central weighting, while 'linear' weights points equally across the window.
   * - Iterations
     - iterations
     - scalar
     - 1
     - 
     - Number of successive smoothing passes (1–10); additional iterations progressively remove more noise at the cost of further peak attenuation — default is 1.
   * - Order Of Fit
     - orderof_fit
     - scalar
     - 1
     - 
     - Polynomial order used for the local least-squares fit within each window (1–5); order 1 is linear (maximum smoothing), higher orders better preserve curve features — default is 1.

Outputs
-------

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   :widths: 20 20 20 20

   * - Label
     - ID
     - Type
     - Description
   * - curve_savitsky_golay_smooth_output_1
     - curve_savitsky_golay_smooth_output_1
     - vector
     - Smoothed output curve (x/y vector) with the same x-axis as the input and y-values replaced by the Savitzky-Golay filtered signal.

Disciplines
-----------

- data.curve.transform
- data.signal_processing

Runnable example
----------------

A runnable example is registered for this worker. Open the example workflow on the d3VIEW canvas: `/api/workflow/example?id=curve_savitsky_golay_smooth <https://www.d3view.com/api/workflow/example?id=curve_savitsky_golay_smooth>`_

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   Auto-generated from <code>transformation</code> schema. Worker id: <code>curve_savitsky_golay_smooth</code>. Schema hash: <code>873b74de0bcd</code>. Hand-curated docs in <code>workerexamples/</code> override this page when present.
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