1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165
|
/*=========================================================================
*
* Copyright NumFOCUS
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0.txt
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*=========================================================================*/
#ifndef itkSingleValuedVnlCostFunctionAdaptor_h
#define itkSingleValuedVnlCostFunctionAdaptor_h
#include "itkSingleValuedCostFunction.h"
#include "vnl/vnl_cost_function.h"
#include "ITKOptimizersExport.h"
namespace itk
{
/** \class SingleValuedVnlCostFunctionAdaptor
* \brief This class is an Adaptor that allows to pass
* itk::SingleValuedCostFunctions to vnl_optimizers expecting
* a vnl_cost_function.
*
* This class returns a single valued.
*
* \ingroup Numerics Optimizers
* \ingroup ITKOptimizers
*/
class ITKOptimizers_EXPORT SingleValuedVnlCostFunctionAdaptor : public vnl_cost_function
{
public:
/** InternalParametersType type alias. */
using InternalParametersType = vnl_vector<double>;
/** InternalMeasureType type alias. */
using InternalMeasureType = double;
/** InternalGradientType type alias. */
using InternalDerivativeType = vnl_vector<double>;
/** Parameters of the SingleValuedCostFunction */
using ParametersType = SingleValuedCostFunction::ParametersType;
/** Derivatives of the SingleValuedCostFunction */
using DerivativeType = SingleValuedCostFunction::DerivativeType;
/** Type of the SingleValuedCostFunction value */
using MeasureType = SingleValuedCostFunction::MeasureType;
/** Scales type alias */
using ScalesType = Array<double>;
/** Constructor with size */
SingleValuedVnlCostFunctionAdaptor(unsigned int spaceDimension);
/** Set the CostFunction deriving from SingleValuedCostFunction */
void
SetCostFunction(SingleValuedCostFunction * costFunction)
{
m_CostFunction = costFunction;
}
/** Get the CostFunction deriving from SingleValuedCostFunction */
const SingleValuedCostFunction *
GetCostFunction() const
{
return m_CostFunction;
}
/** Delegate computation of the value to the CostFunction. */
InternalMeasureType
f(const InternalParametersType & inparameters) override;
/** Delegate computation of the gradient to the costFunction. */
void
gradf(const InternalParametersType & inparameters, InternalDerivativeType & gradient) override;
/** Delegate computation of value and gradient to the costFunction. */
void
compute(const InternalParametersType & x, InternalMeasureType * fun, InternalDerivativeType * g) override;
/** Convert external derivative measures into internal type */
void
ConvertExternalToInternalGradient(const DerivativeType & input, InternalDerivativeType & output) const;
/** Set current parameters scaling. */
void
SetScales(const ScalesType & scales);
/** Set/Get Negate cost function. The purpose of this boolean flag is to make
* possible to take certain VNL optimizers that are only minimizers, and use
* them for maximizing functions. When the boolean flag is set to true, the
* values returned by GetValue in the internal ITK cost function will be
* multiplied by -1 before returning it in the f() function. Similar
* operations will be done for the gradf() and compute() methods. When the
* boolean flag is set to false, then the values returned by the ITK cost
* function will be passed unchanged to the VNL optimizers. */
void
SetNegateCostFunction(bool flag);
bool
GetNegateCostFunction() const;
void
NegateCostFunctionOn()
{
m_NegateCostFunction = true;
}
void
NegateCostFunctionOff()
{
m_NegateCostFunction = false;
}
/** This AddObserver method allows to simulate that this class derives from
* an itkObject for the purpose of reporting iteration events. The goal of
* this method is to allow ITK-vnl optimizer adaptors to get iteration events
* despite the fact that VNL does not provide callbacks. */
unsigned long
AddObserver(const EventObject & event, Command *) const;
/** Return the value of the last evaluation to the value of the cost function.
* Note that this method DOES NOT triggers a computation of the function or
* the derivatives, it only returns previous values. Therefore the values here
* are only valid after you invoke the f() or gradf() methods. */
const MeasureType &
GetCachedValue() const;
const DerivativeType &
GetCachedDerivative() const;
const ParametersType &
GetCachedCurrentParameters() const;
protected:
/** This method is intended to be called by the derived classes in order to
* notify of an iteration event to any Command/Observers */
void
ReportIteration(const EventObject & event) const;
private:
/** Get current parameters scaling. */
itkGetConstReferenceMacro(InverseScales, ScalesType);
SingleValuedCostFunction::Pointer m_CostFunction{};
bool m_ScalesInitialized{};
ScalesType m_InverseScales{};
bool m_NegateCostFunction{};
Object::Pointer m_Reporter{};
mutable MeasureType m_CachedValue{};
mutable DerivativeType m_CachedDerivative{};
mutable ParametersType m_CachedCurrentParameters{};
}; // end of Class CostFunction
} // end namespace itk
#endif
|