kinextract.fh3_fortran_like

kinextract.fh3_fortran_like(w: ndarray) → ndarray[source]

Third-order Gauss-Hermite basis polynomial, legacy Fortran normalization.

Evaluates the h3 basis function used by the original Fortran pipeline (pallmc.f-style convention), which differs by a numerical normalization factor from the van der Marel & Franx (1993) polynomial used elsewhere in this package (see gauss_hermite_losvd_model_ho()). Used inside gauss_hermite_losvd_model() to build the GH LOSVD model and by fit_losvd_gauss_hermite() to recover h3 in the fortran convention.

Parameters:: w (ndarray) – Standardized velocity, w = (v - V) / sigma (dimensionless).
Returns:: Value of the fortran-convention H3 basis polynomial at each w.
Return type:: ndarray