nifty8.operators.simplify_for_const module

class ConstCollector

Bases: object

__init__()

add(const, fulldom)

property constfield

mult(const, fulldom)

class ConstantEnergyOperator(output)

Bases: EnergyOperator

Operator which has a scalar domain as target domain.

It is intended as an objective function for field inference. It can implement a positive definite, symmetric form (called metric) that is used as curvature for second-order minimizations.

Examples

• Information Hamiltonian, i.e. negative-log-probabilities.

• Gibbs free energy, i.e. an averaged Hamiltonian, aka Kullback-Leibler divergence.

__init__(output)

apply(x)

Applies the operator to a Field, MultiField or Linearization.

Parameters:

x (nifty8.field.Field, nifty8.multi_field.MultiField,) – or nifty8.linearization.Linearization Input on which the operator shall act. Needs to be defined on domain. If x`is a :class:`nifty8.linearization.Linearization, apply returns a new nifty8.linearization.Linearization contining the result of the operator application as well as its Jacobian, evaluated at x.

class ConstantLikelihoodEnergyOperator(output)

Bases: LikelihoodEnergyOperator

Represent a negative log-likelihood.

The input to the Operator are the parameters of the negative log-likelihood. Unlike a general EnergyOperator, the metric of a LikelihoodEnergyOperator is the Fisher information metric of the likelihood.

__init__(output)

class ConstantOperator(output, domain={})

Bases: Operator

Transforms values defined on one domain into values defined on another domain, and can also provide the Jacobian.

__init__(output, domain={})

__repr__()

Return repr(self).

apply(x)

Applies the operator to a Field, MultiField or Linearization.

Parameters:

x (nifty8.field.Field, nifty8.multi_field.MultiField,) – or nifty8.linearization.Linearization Input on which the operator shall act. Needs to be defined on domain. If x`is a :class:`nifty8.linearization.Linearization, apply returns a new nifty8.linearization.Linearization contining the result of the operator application as well as its Jacobian, evaluated at x.

class InsertionOperator(target, cst_field)

Bases: Operator

Transforms values defined on one domain into values defined on another domain, and can also provide the Jacobian.

__init__(target, cst_field)

__repr__()

Return repr(self).

apply(x)

Applies the operator to a Field, MultiField or Linearization.

Parameters:

x (nifty8.field.Field, nifty8.multi_field.MultiField,) – or nifty8.linearization.Linearization Input on which the operator shall act. Needs to be defined on domain. If x`is a :class:`nifty8.linearization.Linearization, apply returns a new nifty8.linearization.Linearization contining the result of the operator application as well as its Jacobian, evaluated at x.