sheap.Profiles.ProfileConstraintMaker module

Profile Constraint Maker

This module defines the ProfileConstraintMaker, the central routine in sheap for generating initial values and bounds of profile parameters associated with each SpectralLine.

The constraint sets are specific to the type of profile being modeled: - Continuum profiles (e.g. powerlaw, linear, broken powerlaw, Balmer continuum) - Emission line profiles (e.g. gaussian, lorentzian, skewed) - Composite profiles such as SPAF (Sum of Profiles with Adjustable Fractions) - Template profiles (e.g. Fe templates, Balmer high-order templates, host MILES)

Returned objects are ProfileConstraintSet instances, which encapsulate: - Initial parameter values - Upper and lower bounds - Profile name - Parameter names - The callable profile function

Notes

  • Constraints are informed by physically motivated defaults such as

    velocity FWHM limits, Doppler shift limits, and expected amplitude scales.

  • SPAF and template profiles require additional metadata (subprofiles,

    canonical wavelengths, or template info).

  • The balmercontinuum case uses raw parameterization

    (T_raw, tau_raw, v_raw) with transformations applied in the profile.

Examples

from sheap.Core import SpectralLine, FittingLimits
from sheap.Profiles.profile_handler import ProfileConstraintMaker

sp = SpectralLine(line_name="Halpha", center=6563.0,
                region="narrow", component=1,
                amplitude=1.0, profile="gaussian")
limits = FittingLimits(upper_fwhm_kms=5000, lower_fwhm_kms=200,
                    vshift_kms=600, max_amplitude=100)
constraints = ProfileConstraintMaker(sp, limits)

print(constraints.init, constraints.upper, constraints.lower)
ProfileConstraintMaker(sp, limits, subprofile=None, local_profile=None)[source]

Compute initial values and bounds for the profile parameters of a spectral line.

Parameters:

  • cfg – SpectralLine configuration.

  • limits (FittingLimits) – Kinematic constraints (FWHM and center shift in km/s).

  • profile – Default profile if cfg.profile is None.

  • subprofile (str | None) – Sub-profile function to use within compound models like SPAF.

  • sp (SpectralLine)

  • local_profile (callable | None)

Returns:

Contains initial values, bounds, profile type, and parameter param_names.

Return type:

ProfileConstraintSet