.. _auto_curves_offset_to_change:

*OFFSET CURVES ALONG X WHEN THE INITIAL VALUE CHANGES BASED ON THE RATIO PROVIDED*
==================================================================================

Detects the point where each input curve's initial value changes (using a derivative-based threshold) and offsets all subsequent X-values by the magnitude of that change, scaled by the provided factor. Use this worker to time-align or zero-reference curves whose meaningful signal begins after an initial transient or ramp.

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

Classification: **process**.

Tagged: ``change_detection``, ``curve_alignment``, ``derivative``, ``offset``, ``signal_alignment``, ``time_shift``, ``x-offset``.

Inputs
------

.. list-table::
   :header-rows: 1
   :widths: 20 20 20 20 20 20

   * - Label
     - ID
     - Type
     - Default
     - Required
     - Description
   * - Curves
     - curvestobeoffset
     - vector
     - —
     - 
     - One or more X-Y curves (vector type) to be processed; each curve will be individually inspected for its change point and offset accordingly.
   * - Ratio
     - ratio
     - float
     - 0.025
     - 
     - Fractional threshold relative to the curve's max value used to detect the onset of change; smaller values (e.g. 0.01) catch subtle changes while larger values (e.g. 0.1) ignore small fluctuations — default is 0.025.
   * - Order Of Derivative
     - order
     - float
     - 1
     - 
     - Order of the derivative used for change detection; default is 1 (first-order derivative), which identifies the point of steepest initial slope change.
   * - Offset Scale Factor
     - scale_factor
     - float
     - 1
     - 
     - Multiplier applied to the X-offset shift; positive values (default 1.0) shift data to the right, negative values shift to the left.

Outputs
-------

.. list-table::
   :header-rows: 1
   :widths: 20 20 20 20

   * - Label
     - ID
     - Type
     - Description
   * - curves_offset_to_change_output_1
     - curves_offset_to_change_output_1
     - vector
     - Collection of X-Y curves with the same shape as the inputs but with X-values shifted from the detected change point onward, aligned to the onset of the meaningful 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=curves_offset_to_change <https://www.d3view.com/api/workflow/example?id=curves_offset_to_change>`_

.. raw:: html

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   Auto-generated from <code>transformation</code> schema. Worker id: <code>curves_offset_to_change</code>. Schema hash: <code>1443793b06b7</code>. Hand-curated docs in <code>workerexamples/</code> override this page when present.
   </p>