CenteredFiniteDifferenceGradient¶
-
class
CenteredFiniteDifferenceGradient
(*args)¶ First order centered finite-difference scheme.
- Available constructors:
CenteredFiniteDifferenceGradient(epsilon, evalImpl)
CenteredFiniteDifferenceGradient(step, evalImpl)
Parameters: - evalImpl :
EvaluationImplementation
Implementation of the evaluation of a function.
- epsilon : float, sequence of float
Finite difference steps for each dimension.
- step :
FiniteDifferenceStep
Defines how finite difference steps values are computed.
Notes
CenteredFiniteDifferenceGradient provides a first order centered finite- difference scheme:
Examples
>>> import openturns as ot >>> formulas = ['x1 * sin(x2)', 'cos(x1 + x2)', '(x2 + 1) * exp(x1 - 2 * x2)'] >>> myFunc = ot.SymbolicFunction(['x1', 'x2'], formulas) >>> epsilon = [0.01]*2 >>> myGradient = ot.CenteredFiniteDifferenceGradient(epsilon, myFunc.getEvaluation()) >>> inPoint = [1.]*2 >>> print(myGradient.gradient(inPoint)) [[ 0.841471 -0.909282 0.735771 ] [ 0.540293 -0.909282 -1.10366 ]]
Methods
getCallsNumber
()Accessor to the number of times the gradient has been called. getClassName
()Accessor to the object’s name. getEpsilon
()Get the finite difference steps. getEvaluation
()Get the implementation of the evaluation of the function. getFiniteDifferenceStep
()Get the finite difference step. getId
()Accessor to the object’s id. getInputDimension
()Get the input dimension. getMarginal
(*args)Accessor to the gradient implementation of a specific output. getName
()Accessor to the object’s name. getOutputDimension
()Get the output dimension. getParameter
()Accessor to the parameter values. getShadowedId
()Accessor to the object’s shadowed id. getVisibility
()Accessor to the object’s visibility state. gradient
(inP)Get the gradient at some point. hasName
()Test if the object is named. hasVisibleName
()Test if the object has a distinguishable name. isActualImplementation
()Accessor to the validity flag. setFiniteDifferenceStep
(finiteDifferenceStep)Set the finite difference step. setName
(name)Accessor to the object’s name. setParameter
(parameter)Accessor to the parameter values. setShadowedId
(id)Accessor to the object’s shadowed id. setVisibility
(visible)Accessor to the object’s visibility state. -
__init__
(*args)¶ Initialize self. See help(type(self)) for accurate signature.
-
getCallsNumber
()¶ Accessor to the number of times the gradient has been called.
Returns: - calls_number : int
Integer that counts the number of times the gradient has been called since its creation.
-
getClassName
()¶ Accessor to the object’s name.
Returns: - class_name : str
The object class name (object.__class__.__name__).
-
getEpsilon
()¶ Get the finite difference steps.
Returns: - epsilon :
Point
Finite difference steps for each dimension.
- epsilon :
-
getEvaluation
()¶ Get the implementation of the evaluation of the function.
Returns: - evalImpl :
EvaluationImplementation
Implementation of the evaluation of a function.
- evalImpl :
-
getFiniteDifferenceStep
()¶ Get the finite difference step.
Returns: - step :
FiniteDifferenceStep
Defines how finite difference steps values are computed.
- step :
-
getId
()¶ Accessor to the object’s id.
Returns: - id : int
Internal unique identifier.
-
getInputDimension
()¶ Get the input dimension.
Returns: - dimension : int
Input dimension.
-
getMarginal
(*args)¶ Accessor to the gradient implementation of a specific output.
Parameters: - i : integer
Integer corresponding to the output (Care: it starts at 0).
- indices : sequence of integer
The set of indices for which the outputs are extracted.
Returns: - gradientImplementation :
GradientImplementation
A gradient implementation restricted to its compenents functions which indices are i or indices.
-
getName
()¶ Accessor to the object’s name.
Returns: - name : str
The name of the object.
-
getOutputDimension
()¶ Get the output dimension.
Returns: - dimension : int
Output dimension.
-
getShadowedId
()¶ Accessor to the object’s shadowed id.
Returns: - id : int
Internal unique identifier.
-
getVisibility
()¶ Accessor to the object’s visibility state.
Returns: - visible : bool
Visibility flag.
-
gradient
(inP)¶ Get the gradient at some point.
Parameters: - point : sequence of float
Point where the gradient is computed.
Returns: - gradient :
Matrix
Transposed Jacobian matrix evaluated at point.
-
hasName
()¶ Test if the object is named.
Returns: - hasName : bool
True if the name is not empty.
-
hasVisibleName
()¶ Test if the object has a distinguishable name.
Returns: - hasVisibleName : bool
True if the name is not empty and not the default one.
-
isActualImplementation
()¶ Accessor to the validity flag.
Returns: - is_impl : bool
Whether the implementation is valid.
-
setFiniteDifferenceStep
(finiteDifferenceStep)¶ Set the finite difference step.
Parameters: - step :
FiniteDifferenceStep
Defines how finite difference steps values are computed.
- step :
-
setName
(name)¶ Accessor to the object’s name.
Parameters: - name : str
The name of the object.
-
setParameter
(parameter)¶ Accessor to the parameter values.
Parameters: - parameter : sequence of float
The parameter values.
-
setShadowedId
(id)¶ Accessor to the object’s shadowed id.
Parameters: - id : int
Internal unique identifier.
-
setVisibility
(visible)¶ Accessor to the object’s visibility state.
Parameters: - visible : bool
Visibility flag.