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fit

spectrafit_solver

Function fit 

Source 
pub fn fit(
    graph: &FitGraphSpec,
    datasets: Vec<MeasurementSpec>,
    options: &FitOptionsSpec,
) -> Result<FitResultSpec, CoreError>
Expand description

Run a fit of graph against datasets using the solver named by options.solver (see Solver::parse for the accepted strings: lm, lm-legacy, trf, geodesic, dogleg, newton-cg, irls[:weight], global, varpro, auto).

The LM family (lm, lm-legacy, trf, geodesic) plus the trust-region methods (dogleg, newton-cg) and auto’s non-VarPro fallback share one pre-solve/solve/post-fit path through this function. irls, global, and varpro are routed to their own modules/crates in dispatch_solver and return before that shared path runs.

Returns a fully populated FitResultSpec including parameter values, standard errors, covariance matrix, and goodness-of-fit statistics.

§Errors

Returns CoreError when:

  • options.solver does not parse (unrecognised solver name, or an unrecognised irls:<weight> weight-function name) — Solver::parse.
  • The routed non-LM-family solver fails: irls (crate::irls::solve_irls), global (differential evolution), or varpro (not separable, tied parameters present, or per-dataset scoping unsupported).
  • Graph compilation or the initial model evaluation fails (malformed graph, a free-key/parameter lookup miss, or a model evaluation error) — prepare_lm_pre_solve.
  • The LM-family solve itself fails or produces a numerically unusable result (e.g. ill-conditioned Jacobian) that maps to CoreError::Solver.
  • options.eta is set alongside solver="dogleg" / "newton-cg" but is not finite and in [0.0, 0.25) — SolverError::InvalidEta.
  • Post-fit assembly fails while re-evaluating the model or its Jacobian at the solution — postfit::assemble_result.