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 meaningfully deviates from Curve 1, using configurable y- and x-tolerance thresholds. Use this worker to detect onset points such as yield, separation, or bifurcation between a reference and a test curve.

When to use

Classification: process.

Tagged: curve_comparison, curve_deviation, deviation_detection, onset_detection, tolerance, transformations, x_at_deviation.

Inputs

Label ID Type Default Required Description
Curve 1 curve1 vector   Reference curve (Curve 1) supplied as an x-y vector; serves as the baseline against which Curve 2 is compared.
Curve 2 curve2 vector   Test curve (Curve 2) supplied as an x-y vector; deviations from Curve 1 are measured on this curve.
Y Tolerance y_tol scalar 0.01   Fractional y-deviation threshold: a y-difference is flagged as deviation when it exceeds y_tol × (YMAX − YMIN); defaults to 0.01 (1 % of the y-range).
X Tolerance x_tol scalar 0.01   Fractional x-persistence threshold: the y-deviation must sustain over x_tol × (XMAX − XMIN) before it is declared a true deviation; defaults to 0.01 (1 % of the x-range).
Y-Tolerance y_tol_for_zero scalar 0.25   Proximity multiplier applied to y_tol to define how close the two curves must be before the search for deviation begins; defaults to 0.25 (i.e., the curves must agree within 25 % of y_tol).
Auto-Adjust Tolerance auto_adjust_tol list no   Set to ‘yes’ to automatically reduce the y- and x-tolerances and retry when the supplied values are larger than the data can resolve; defaults to ‘no’.
Number Of Auto Adjusts num_auto_adjusts scalar 3   Number of times the tolerances are reduced by 50% each time
Start after this X x_start scalar 0.0   If the value is crossover, we find the first crossover point

Outputs

Label ID Type Description
curve_subtract_from_output curve_subtract_from_output scalar Scalar x-value (in the same units as the input curves’ x-axis) at which Curve 2 first deviates from Curve 1 according to the specified tolerances.

Disciplines

  • data.curve.pair

Runnable example

A runnable example is registered for this worker. Open the example workflow on the d3VIEW canvas: /api/workflow/example?id=curve_get_x_at_deviation


Auto-generated from transformation schema. Worker id: curve_get_x_at_deviation. Schema hash: ea8809d8e92f. Hand-curated docs in workerexamples/ override this page when present.