Improvements for helicity, q(r) discritization, and d_phi advance

[chandrarn]

Improvements to ensure agreement with empirical C-Mod data. The improved d_phi step is necessary for accurate filament structures for non-interger m/n modes. The fix corrects an assumption that d_l_theta = r theta, which is only true in the limiting case of circular cross section.

[Copilot]

Pull request overview

This pull request implements improvements to the magnetic geometry calculations to better match empirical C-Mod data, specifically addressing helicity handling, q(r) discretization, and the d_phi advance calculation.

Changes:

• Switched from interpolation to smoothing splines for q(psi) and F(psi) to avoid discretization jumps
• Added helicity_sign parameter to control the sign of the helicity in filament tracing
• Improved d_phi calculation to use actual segment lengths instead of assuming circular cross-sections

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 19 comments.

File	Description
synthwave/magnetic_geometry/equilibrium_field.py	Replaced interpolating splines with smoothing splines for q(psi) and F(psi); added lam parameter for smoothing control; changed ValueError to SyntaxError in error handling
synthwave/magnetic_geometry/filaments.py	Added helicity_sign parameter to _trace method; updated _Z_a and psi_prime_a functions to use helicity_sign; implemented new _d_phi_dl function using actual segment lengths; increased Newton solver iterations

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[Copilot]

@chandrarn I've opened a new pull request, #2, to work on those changes. Once the pull request is ready, I'll request review from you.

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 11 comments.

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[chandrarn]

@copilot open a new pull request to apply changes based on the comments in this thread

[Copilot]

@chandrarn I've opened a new pull request, #3, to work on those changes. Once the pull request is ready, I'll request review from you.

[chandrarn]

@copilot open a new pull request to apply changes based on the comments in this thread

[Copilot]

@chandrarn I've opened a new pull request, #4, to work on those changes. Once the pull request is ready, I'll request review from you.

[chandrarn]

@copilot open a new pull request to apply changes based on the comments in this thread

[Copilot]

@chandrarn I've opened a new pull request, #5, to work on those changes. Once the pull request is ready, I'll request review from you.

[ZanderKeith]

Fix linting and I'll approve.

[chandrarn]

pre-commit lint checks