.. _auto_curve_failure_stress_strain:

*COMPUTE THE FAILURE STRESS STRAIN VALUES*
==========================================

Detects the failure point on a stress-strain curve by analysing slope changes over rolling segments and returns the failure stress, strain, or both. Use this worker to extract fracture/necking onset coordinates from a uniaxial or shear coupon curve without manual inspection.

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

Classification: **process**.

Tagged: ``coupon``, ``curve_analysis``, ``failure_point``, ``failure_stress_strain``, ``fracture``, ``necking``, ``segment_slope``, ``stress_strain``.

Inputs
------

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

   * - Label
     - ID
     - Type
     - Default
     - Required
     - Description
   * - Curve From Which The Failure Point Is To Be Extracted
     - curvefromwhichthefailurepointistobeextracted
     - vector
     - —
     - 
     - Input stress-strain (or force-displacement) curve from which the failure point is to be extracted; provide as an XY vector — leave empty only if the curve is injected directly by an upstream worker.
   * - Segment Length
     - ratio
     - string
     - 0.05
     - 
     - Rolling-segment length expressed as a fraction of the total curve length (dimensionless, 0–1); controls the sensitivity of the slope-change detection — smaller values (e.g. 0.02) are more sensitive to local drops, larger values (e.g. 0.10) smooth out noise; defaults to 0.05.
   * - Return Type
     - retyrn_type
     - string
     - x
     - 
     - Selects what the worker returns at the detected failure point: 'x' = failure strain only, 'y' = failure stress only, 'slope' = slope at failure, 'xy' = strain and stress pair, 'xys' = strain, stress, and slope; defaults to 'x'.

Outputs
-------

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

   * - Label
     - ID
     - Type
     - Description
   * - Failure Stress Strain
     - failure_stress_strain
     - scalar
     - Scalar (or comma-separated pair/triple) representing the failure point value(s) requested via return_type: a single numeric strain or stress, or an 'x,y' / 'x,y,slope' string depending on the selected return type.

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

- data.curve.transform
- engineering.material.characterization
- engineering.material.failure
- engineering.material.specimen

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

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

.. raw:: html

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   Auto-generated from <code>transformation</code> schema. Worker id: <code>curve_failure_stress_strain</code>. Schema hash: <code>aaf08878a6ab</code>. Hand-curated docs in <code>workerexamples/</code> override this page when present.
   </p>