.. _auto_curve_get_necking_ratios:

*GET RATIO OF NECKING STRESS BETWEEN THE TWO ENG. STRESS VS STRAIN CURVES*
==========================================================================

Computes the ratio of necking stress between two engineering stress-vs-strain curves (e.g., test vs. simulation). An optional peak-matching mode aligns the curves at the engineering peak or true necking point before computing ratios, including post-necking regions if requested.

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

Classification: **process**.

Tagged: ``curve_comparison``, ``engineering_stress_strain``, ``material_characterization``, ``necking``, ``necking_point``, ``peak_match``, ``stress_ratio``.

Inputs
------

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

   * - Label
     - ID
     - Type
     - Default
     - Required
     - Description
   * - Eng Stress vs Strain Curve 1
     - eng_ss_1
     - vector
     - —
     - 
     - First engineering stress vs. strain curve (e.g., physical test coupon result); accepts a single curve or the first curve of a CurveGroup; strain on x-axis (mm/mm), stress on y-axis (MPa).
   * - Eng Stress vs Strain Curve 2
     - eng_ss_2
     - vector
     - —
     - 
     - Second engineering stress vs. strain curve to compare against the first (e.g., simulation output); accepts a single curve or the first curve of a CurveGroup; must share the same axis units as eng_ss_1.
   * - Type of Peak Match
     - peak_match_type
     - select
     - none
     - 
     - Controls how the two curves are aligned before ratio computation: 'none' skips alignment, 'eng_peak' aligns at the first engineering stress peak, 'true_necking_point' aligns at the true necking point (intersection of true stress and its derivative), 'eng_peak_post_neck' also matches post-necking region from the engineering peak, and 'true_necking_post_neck' also matches the post-necking region from the true necking point; defaults to 'none'.

Outputs
-------

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

   * - Label
     - ID
     - Type
     - Description
   * - Ratios
     - ratio
     - keyvalue
     - Key-value map of computed necking stress ratios between the two curves (e.g., ratio at peak, at necking point), reflecting the selected peak_match_type alignment strategy.

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

- data.correlation
- data.curve.pair
- engineering.material.characterization

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

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

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   Auto-generated from <code>transformation</code> schema. Worker id: <code>curve_get_necking_ratios</code>. Schema hash: <code>07b95120f17f</code>. Hand-curated docs in <code>workerexamples/</code> override this page when present.
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