Match¶

class specmatchemp.match.Match(target, reference, mode='default', opt='nelder')¶

The Match class used for matching two spectra

target¶: Spectrum – Target spectrum

reference¶: Spectrum – Reference spectrum

modified¶: Spectrum – Modified reference, after broadening and fitting a spline to correct for continuum differences

spl¶: np.ndarray – Spline used to fit continuum level

best_params¶: lmfit.Parameters – Parameters used to create the best match.

best_chisq¶: float – Chi-squared from the best match

Parameters:	target (Spectrum) – Target spectrum reference (Spectrum) – Reference spectrum mode – default (unnormalized chi-square), normalized (normalized chi-square) opt – lm (Levenberg-Marquadt optimization), nelder (Nelder-Mead)

best_fit(params=None)¶: Calculates the best fit model by minimizing over the parameters: - spline fitting to the continuum - rotational broadening

best_residuals()¶

Returns the residuals between the target spectrum and best-fit spectrum.

Returns:	np.ndarray

broaden(vsini, spec)¶

Applies a broadening kernel to the given spectrum (or error)

Parameters:	vsini (float) – vsini to determine width of broadening spec (Spectrum) – spectrum to broaden
Returns:	Broadened spectrum
Return type:	broadened (Spectrum)

create_model(params)¶: Creates a tweaked model based on the parameters passed, based on the reference spectrum. Stores the tweaked model in spectra.s_mod and serr_mod.

get_spline_positions()¶

Wrapper function for getting spline positions

Returns:	knotx (np.ndarray)

load_params(params)¶: Method to create a model based on pre-determined parameters, storing it as the best fit model.

objective(params)¶

Objective function evaluating goodness of fit given the passed parameters.

Parameters:	params –
Returns:	Reduced chi-squared value between the target spectra and the model spectrum generated by the parameters

classmethod read_hdf(infile)¶

Reads the Match object from an HDF file.

Parameters:	infile (str or h5 file) – Input path or file handle.

to_hdf(outfile)¶

Saves the Match object to an hdf file.

Parameters:	outfile (str or h5 file) – Output path or file handle.

class specmatchemp.match.MatchLincomb(target, refs, vsini, mode='default', ref_chisq=None)¶

MatchLincomb class used to match a linear combination of spectra to match a target spectrum.

target¶: Spectrum – Target spectrum

refs¶: list of Spectrum – List of reference spectra

vsini¶: np.ndarray – Array of vsini used to broaden the reference spectra.

spl¶: np.ndarray – Spline used for continuum fitting.

modified¶: Spectrum – Best linear combination of spectra.

best_params¶: lmfit.Parameters – Parameters used to create the best match.

best_chisq¶: floatt – Chi-squared from the best match.

Parameters:	target (Spectrum) – Target spectrum refs (list of Spectrum) – Array of reference spectra vsini (np.ndarray) – array containing vsini broadening for each reference spectrum

best_fit()¶: Calculates the best fit model by minimizing over the parameters: - Coefficients of reference spectra - spline fitting to the continuum - rotational broadening

create_model(params)¶: Creates a tweaked model based on the parameters passed, based on the reference spectrum. Stores the tweaked model in spectra.s_mod and serr_mod.

get_lincomb_coeffs()¶

Wrapper function to get lincomb coefficients from MatchLincomb object

Returns:	coeffs (np.ndarray)

get_vsini()¶

Wrapper function to get vsini list from MatchLincomb object

Returns:	vsini (np.ndarray)