GET FIT SLOPES¶
Segments an input curve into piecewise linear regions and extracts the best-fit slope for each segment using a sliding-window linear regression. Use this worker to identify dominant slope regimes in stress-strain, force-displacement, or similar engineering curves, with optional filtering to a target slope value.
When to use¶
Classification: process.
Tagged: curve, digitization, fit_slopes, linear_fit, piecewise, r2, regression, segmentation.
Inputs¶
| Label | ID | Type | Default | Required | Description |
|---|---|---|---|---|---|
| Input Curve | input_curve | vector | — | The XY curve to analyse (e.g. force-displacement or stress-strain); supplied as a two-column vector — leave empty only when chaining from an upstream curve output. | |
| Num Dig | num_dig | integer | 1000 | Number of uniformly spaced points used to re-digitize the input curve before segmentation; default 1000 — increase for high-frequency curves, decrease for speed. | |
| Segment Length Ratio | segment_length_ratio | integer | 0.01 | Fraction of the total re-digitized point count that defines the sliding-window width for local linear fitting (e.g. 0.01 = 1 %); smaller values yield finer slope resolution. | |
| Min R2 | r2_limit | integer | 0.95 | Minimum R² goodness-of-fit threshold (0–1) a segment must meet to be retained; default 0.95 — lower to accept noisier linear regions. | |
| Merge Ratio | merge_ratio | integer | 0.025 | Relative tolerance used to merge adjacent segments whose slopes differ by less than this fraction (e.g. 0.025 = 2.5 %); reduces duplicate near-identical slope entries. | |
| Target Slope | target_slope | integer | 0 | Reference slope value around which results are filtered; set to 0 (default) to disable target filtering and return all detected slopes. | |
| Target Percentage | target_percentage | integer | 0.05 | Fractional tolerance around target_slope — only slopes within ±target_percentage of target_slope are returned (e.g. 0.05 = ±5 %); ignored when target_slope is 0. | |
| Maximize Params | maximize_params | scalar | slope,r2 |
Outputs¶
| Label | ID | Type | Description |
|---|---|---|---|
| curve_get_fit_slopes_output_1 | curve_get_fit_slopes_output_1 | dataset | Dataset table of detected piecewise linear segments, each row containing the x-start, x-end, fitted slope, and R² value for that segment, sorted by descending slope·R² score. |
Disciplines¶
- ai_ml.supervised.regression
- data.curve.transform
- data.statistics
- 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_fit_slopes
Auto-generated from transformation schema. Worker id: curve_get_fit_slopes. Schema hash: f1e365ee47b4. Hand-curated docs in workerexamples/ override this page when present.