lsst.gauss2d.fit

gauss2d_fit is a submodule for gauss2d that implements a 2D Gaussian mixture model class, along with its constituent parts, including parameters and data. The Model class can evaluate the likelihood and gradients thereof. gauss2d_fit does not yet provide optimizers, although support for GSL fitters is planned. Users should turn to MultiProFit for access to Python (scipy) optimizers.

Gaussian mixture approximations to the Sersic profile are provided. Use of the GSL library is strongly recommended as it enables nonlinear interpolation of the profile weights, which is necessary to compute accurate derivatives of the likelihood and model for the Sersic index parameter.

Using lsst.gauss2d.fit

Example usage can be found in the unit tests and also in dependent packages, particularly MultiProFit.

Contributing

lsst.gauss2d.fit is developed at https://github.com/lsst-dm/gauss2d_fit. You can find Jira issues for this module under the gauss2d_fit component.

Python API reference

lsst.gauss2d.fit has Python bindings for classes using numpy-based single and double precision arrays. Support for GSL arrays is forthcoming with DM-38617.

lsst.gauss2d.fit Package

Functions

params_unique([params])

sersic_mix_knots([order])

Classes

CentroidParameters

CentroidXParameterD

CentroidYParameterD

Channel

Chromatic

Component

ComponentMixture

DataD

DataF

EllipticalComponent

EvaluatorMode

Members:

FractionalIntegralModel

GaussianComponent

GaussianModelIntegral

GaussianParametricEllipse

GaussianPrior

HessianOptions

IntegralModel

IntegralParameterD

IntegralSize

InterpType

Members:

InverseTransformD

JanskyToABMagTransformD

LimitsD

LinearIntegralModel

LinearSersicMixInterpolator

Log10TransformD

LogTransformD

LogitLimitedTransformD

LogitTransformD

MeanParameterD

ModelD

ModelF

MoffatConcentrationParameterD

NanojanskyToABMagTransformD

ObservationD

ObservationF

ParamFilter

ParameterD

Parametric

ParametricEllipse

ParametricGaussian1D

ParametricModel

Prior

PriorEvaluation

ProperFractionParameterD

PsfModel

RadiusScaleParameterD

ReffXParameterD

ReffYParameterD

RhoParameterD

SersicIndexParameterD

SersicMixComponent

SersicMixComponentIndexParameterD

SersicMixInterpolator

SersicMixValues

SersicParametricEllipse

ShapePrior

ShapePriorOptions

SigmaXParameterD

SigmaYParameterD

SizeXParameterD

SizeYParameterD

Source

StdDevParameterD

TransformD

Unit

UnitNone

UnitTransformD