.. _auto_curve_user_defined:

*CREATE A CURVE WITH CUSTOM DEFINITION*
=======================================

Creates a curve from a user-supplied PHP-style code snippet that returns an array of (x, y) point pairs. Use this worker when a curve cannot be expressed by a standard mathematical template and requires custom procedural logic to generate its data points.

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

Classification: **process**.

Tagged: ``code_editor``, ``curve``, ``custom_curve``, ``php``, ``points``, ``transformation``, ``user_defined``.

Inputs
------

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

   * - Label
     - ID
     - Type
     - Default
     - Required
     - Description
   * - Curve Name
     - curve_name
     - scalar
     - —
     - ✓
     - Display name assigned to the generated curve; used as a label in downstream plots and reports. Accepts any free-text string; leave blank to use the worker default.
   * - Definition
     - definition
     - text
     - <?php $points = array(); $points[] = array( 0, 1 ); // x , y  $points[] = array( 0, 2 ); // x , y //   # the points variable will be used to construct the curve by d3VIEW
     - ✓
     - PHP-style code block that constructs the curve; must populate a $points array of [x, y] pairs (or provide a run() function/class method returning the same structure). Edit in the built-in code editor; the default skeleton shows two sample points to illustrate the expected format.

Outputs
-------

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

   * - Label
     - ID
     - Type
     - Description
   * - Curve
     - curve_def
     - vector
     - The generated curve as an (x, y) vector, built from the point pairs returned by the user-defined code snippet; passed downstream for plotting, transformation, or further analysis.

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

- data.curve.transform

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

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

.. raw:: html

   <hr style="margin-top:2em">
   <p style="font-size:11px;color:#888">
   Auto-generated from <code>transformation</code> schema. Worker id: <code>curve_user_defined</code>. Schema hash: <code>5bd5a52ad281</code>. Hand-curated docs in <code>workerexamples/</code> override this page when present.
   </p>