SimplexLSQFitter

class astropy.modeling.fitting.SimplexLSQFitter

Bases: Fitter

Simplex algorithm and least squares statistic.

Raises:

ModelLinearityError

A linear model is passed to a nonlinear fitter

Attributes Summary

supported_constraints

Methods Summary

__call__(model, x, y[, z, weights, inplace])	Fit data to this model.
objective_function(fps, *args)	Function to minimize.

Attributes Documentation

supported_constraints = ['bounds', 'fixed', 'tied']

Methods Documentation

__call__(model, x, y, z=None, weights=None, *, inplace=False, **kwargs)

Fit data to this model.

Parameters:

modelFittableModel

model to fit to x, y, z

xarray

input coordinates

yarray

input coordinates

zarray, optional

input coordinates

weightsarray, optional

Weights for fitting. For data with Gaussian uncertainties, the weights should be 1/sigma.

kwargspython:dict

optional keyword arguments to be passed to the optimizer or the statistic

maxiterpython:int

maximum number of iterations

accpython:float

Relative error in approximate solution

equivalenciespython:list or python:None, optional, keyword-only

List of additional equivalencies that are should be applied in case x, y and/or z have units. Default is None.

inplacebool, optional

If False (the default), a copy of the model with the fitted parameters set will be returned. If True, the returned model will be the same instance as the model passed in, and the parameter values will be changed inplace.

Returns:

fitted_modelFittableModel

If inplace is False (the default), this is a copy of the input model with parameters set by the fitter. If inplace is True, this is the same model as the input model, with parameters updated to be those set by the fitter.

objective_function(fps, *args)

Function to minimize.

Parameters:

fpspython:list

parameters returned by the fitter

argspython:list

[model, [other_args], [input coordinates]] other_args may include weights or any other quantities specific for a statistic

Notes

The list of arguments (args) is set in the __call__ method. Fitters may overwrite this method, e.g. when statistic functions require other arguments.