.. _auto_curve_interpolate:

*INTERPOLATION VALUES*
======================

Resamples or interpolates a 2-D curve onto a new set of x-axis points using a chosen method (linear, spline, PCHIP, polynomial, Makima, or Kriging). Use this worker whenever you need to densify, respace, or evaluate a curve at specific x-locations before downstream processing.

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

Classification: **process**.

Tagged: ``curve``, ``interpolation``, ``kriging``, ``linear``, ``makima``, ``pchip``, ``polynomial``, ``resample``.

Inputs
------

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

   * - Label
     - ID
     - Type
     - Default
     - Required
     - Description
   * - Curve
     - curve
     - vector
     - —
     - 
     - Input 2-D curve (x/y vector pair) to be interpolated; must be supplied before the worker can execute.
   * - Type Of Interpolation
     - interpolation_type
     - scalar
     - linear
     - 
     - Interpolation algorithm to apply: 'linear' (default), 'pchip' (shape-preserving cubic Hermite), 'polynomial', 'spline' (cubic spline), 'makima' (modified Akima), or 'kriging'; leave as 'linear' for most resampling tasks.
   * - Constant 1
     - c1
     - float
     - 100
     - 
     - Primary control parameter: an integer specifying the total number of output points (default 100), a range string in 'min:max:step' format, or a comma-separated list of explicit x-values 'p1,p2,p3'.
   * - Constant 2
     - c2
     - float
     - 0
     - 
     - Secondary control parameter used in conjunction with C1 when specifying a range or polynomial degree; leave at default (0) when C1 already fully defines the output x-grid.
   * - Constant 3
     - c3
     - float
     - 0
     - 
     - Tertiary control parameter for additional method-specific tuning (e.g. polynomial degree); leave at default (0) unless the chosen interpolation type requires it.
   * - Use Existing
     - use_existing
     - scalar
     - no
     - 
     - When set to 'yes', original curve points that fall within the min/max range are merged into the output alongside the interpolated points; default is 'no' (purely interpolated grid only).

Outputs
-------

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

   * - Label
     - ID
     - Type
     - Description
   * - curve_interpolate_output_1
     - curve_interpolate_output_1
     - vector
     - Resampled 2-D curve (x/y vector pair) evaluated at the x-locations defined by C1/C2/C3, using the selected interpolation method.

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

- data.curve.transform
- data.signal_processing

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

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

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   Auto-generated from <code>transformation</code> schema. Worker id: <code>curve_interpolate</code>. Schema hash: <code>408d090224b8</code>. Hand-curated docs in <code>workerexamples/</code> override this page when present.
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