.. _auto_curves_get_x_at_deviation:

*RETURN THE X-VALUE FROM WHICH THE CURVE 2 DEVIATES FROM CURVE1*
================================================================

Compares two curves and returns the x-value at which Curve 2 first deviates from Curve 1 beyond specified tolerances. Deviation is detected when the y-difference exceeds a fraction of the y-range and persists over a fraction of the x-range. Use this worker to identify divergence points between a reference curve and a test curve.

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

Classification: **process**.

Tagged: ``crossover``, ``curve_comparison``, ``curve_deviation``, ``divergence_point``, ``tolerance``, ``x_at_deviation``.

Inputs
------

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

   * - Label
     - ID
     - Type
     - Default
     - Required
     - Description
   * - Curve 1
     - curves1
     - vector
     - —
     - 
     - Reference curve (Curve 1) against which Curve 2 is compared; accepts one or more XY vector curves.
   * - Curve 2
     - curves2
     - vector
     - —
     - 
     - Test curve (Curve 2) that is compared against Curve 1 to detect deviation; accepts one or more XY vector curves.
   * - Y Tolerance
     - y_tol
     - scalar
     - 0.05
     - 
     - Fractional y-tolerance threshold: a y-difference larger than y_tol × (YMAX − YMIN) is flagged as a deviation; default is 0.05 (5% of the y-range).
   * - X Tolerance
     - x_tol
     - scalar
     - 0.05
     - 
     - Fractional x-persistence threshold: the deviation must sustain over x_tol × (XMAX − XMIN) before it is confirmed; default is 0.05 (5% of the x-range).
   * - Y Tol For Zero
     - y_tol_for_zero
     - scalar
     - 0.25
     - 
     - Multiplier applied to y_tol to define how closely the two curves must agree before a deviation can be declared; default is 0.25 (i.e. the starting closeness threshold is 0.25 × y_tol × y-range).
   * - Start after this X
     - x_start
     - scalar
     - 0.0
     - 
     - X-value from which the deviation search begins; pass 'crossover' to start from the first crossover point, or a numeric value (default 0.0) to start from a fixed x-position.

Outputs
-------

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

   * - Label
     - ID
     - Type
     - Description
   * - Deviations
     - curves_deviation_output1
     - dataset
     - Dataset containing the detected deviation results, including the x-value at which Curve 2 first deviates from Curve 1 for each curve pair.

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

- data.curve.pair
- data.curve.transform
- data.statistics

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

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

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   Auto-generated from <code>transformation</code> schema. Worker id: <code>curves_get_x_at_deviation</code>. Schema hash: <code>9acf9c08cc41</code>. Hand-curated docs in <code>workerexamples/</code> override this page when present.
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