COMPUTE THE POINT AT WHICH THE Y-VALUE DROPS TO ZERO OR STARTS TO DECLINE AT THE END OF THE CURVE. USEFUL FOR MATERIAL FAILURE ETC¶
Identifies the failure point on one or more curves by locating the position of the steepest negative slope (minimum derivative) near the end of the curve, optionally verifying that the Y-value subsequently stays below a specified ratio of the maximum. Useful for extracting material failure strains, ultimate loads, or any critical drop-off point from stress-strain or force-displacement curves.
When to use¶
Classification: process.
Tagged: curve_analysis, drop_detection, failure_point, material_failure, min_derivative, negative_slope, stress_strain.
Inputs¶
| Label | ID | Type | Default | Required | Description |
|---|---|---|---|---|---|
| Curves From Which The Failure Point Is To Be Extracted | curvesfromwhichthefailurepointistobeextracted | vector | — | One or more input curves (e.g., force-displacement or stress-strain) from which the failure point is to be detected; accepts d3VIEW curve vectors. | |
| Ratio | ratio | scalar | — | Dimensionless scalar threshold (0–1): the algorithm searches for the steepest negative slope in the region where the Y-value falls below this fraction of the curve’s maximum Y; defaults to checking the full tail if left blank. | |
| Ensure Sustainability | ensuresustainability | string | no | Set to ‘yes’ to require that the Y-value remains below the ratio threshold after the detected minimum-derivative point, confirming a sustained drop; set to ‘no’ (default) to return the steepest-slope point unconditionally. | |
| Return Type | return_type | string | count | Controls what value is returned at the failure point: ‘xval’ returns the X-axis coordinate (e.g., strain or displacement), ‘yval’ returns the Y-axis coordinate (e.g., stress or force); leave at default ‘count’ to return the point index. | |
| Return previous point to min derivative | returnpreviouspointtominderivative | string | no | Set to ‘yes’ to return the data point immediately before the minimum-derivative location (i.e., the last stable point prior to failure onset); set to ‘no’ (default) to return the value at the minimum-derivative point itself. |
Outputs¶
| Label | ID | Type | Description |
|---|---|---|---|
| curves_failurepoint_min_derivative_output_1 | curves_failurepoint_min_derivative_output_1 | dataset | Dataset containing the extracted failure-point value (X coordinate, Y coordinate, or point index depending on ‘return_type’) for each input curve, one row per curve. |
Disciplines¶
- data.curve.transform
- engineering.material.characterization
- engineering.material.failure
Runnable example¶
A runnable example is registered for this worker. Open the example workflow on the d3VIEW canvas: /api/workflow/example?id=curves_failurepoint_min_derivative
Auto-generated from transformation schema. Worker id: curves_failurepoint_min_derivative. Schema hash: 9d055b1fedb4. Hand-curated docs in workerexamples/ override this page when present.