Repository navigation
PerturbedEquilibrium - FEATURE - Export the per-model and local-window singular-coupling SVDs as Fortran GPEC 1.6 does #631
Description
Fortran GPEC exports a singular-coupling SVD for each of its coupling models, plus a local-window (osing < msing) SVD. PrincetonUniversity/GPEC#330 corrected the exported vectors to W^H·V so that contracting them with the applied field gives the overlap. PrincetonUniversity/GPEC#185 removed a √2 and added units.
Julia exports one dominant-mode SVD of C_resonant_area_weighted_field (PerturbedEquilibrium/ResonantCoupling.jl). Windowing is a post-hoc choice on ResonantCoupling, and the overlap is checked against the solve (runtests_dominant_coupling.jl).
Scope: decide which Fortran exports v2 users need, export them under PerturbedEquilibrium/SingularCoupling/, and test the overlaps against the solve as the existing tests do.
Feature-parity item from the Fortran GPEC 1.6.0 survey in #591; filed so it is tracked once #591 closes.
Activity
logan-nc commentedon Nov 2, 2026
Closing as a deliberate design choice, not a gap. #446 chose not to write per-model or local-window SVDs into
gpec.h5. Instead the run always writes the full coupling matrices (all five models) and the official analysis helper decomposes any of them over any window of rational surfaces, instantly, from the run in memory or from its file:ResonantCoupling,dominant_coupling,rootarea_fieldandcoupling_overlapinPerturbedEquilibrium/ResonantCoupling.jl. Fortran's local-coupling outputs (osing < msing) needed a full new run to change the range of interest. The overlap is checked against the solve inruntests_dominant_coupling.jl. #627 adds a guide section (docs/src/perturbed_equilibrium.md, Other coupling matrices and local windows) showing how to decompose each of the five matrices over any window, and what the result means in each matrix's units.