parabolic cylinder functions

[jorenham]

• pbwa
• pbdv
• pbvv

[Copilot]

Pull Request Overview

This PR adds support for parabolic cylinder functions by implementing three new functions: pbwa, pbdv, and pbvv. These functions compute parabolic cylinder functions W, D, and V respectively, along with their derivatives.

• Adds three new parabolic cylinder function implementations with proper documentation
• Includes test coverage for the new functions using the existing test framework
• Updates build configuration to include the par_cyl.h header

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
src/par_cyl.rs	New module implementing the three parabolic cylinder functions with documentation
src/lib.rs	Exposes the new parabolic cylinder functions in the public API
build.rs	Enables par_cyl.h header and adds function type definitions
tests/test_functions.rs	Adds test coverage and reorganizes macro definitions

Comments suppressed due to low confidence (1)

src/par_cyl.rs:1

• The return value documentation is incorrect. The function returns vv (the function value) and vp (the derivative), but the documentation states 'v: Value of the function' which conflicts with the parameter name v. It should be 'vv: Value of the function' to match the actual return variable.

use crate::bindings;

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