Prerequisite
- Function class
Synopsis
This class takes an arbitrary number of Function objects, and generates a new, single function object. The parameters of the compound object are the union of all the parameters in the input objects.When CompoundFunction is evaluated, the result is the sum of all the individual function values.
Member functions are added with the addFunction() method.
In general the interaction with the function parameters should be through the overall function parameters (i.e. through the parameters of the CompoundFunction). If for any reason you want to set the parameters of an individual function (see e.g. the example in the Fit2D), call consolidate() before and after the actual setting.
Check CombiFunction class for a simple linear combination of function objects
Example
Suppose for some reason we wanted the sum of x^2 plus a gaussian. We could form it as follows:
Polynomial<Float> x2(2);
x[2] = 1.0; // x^2
Gaussian1D<Float> gauss(1.0, 0.0, 1.0); // e^{-x^2}
CompoundParam<Float> sum; // sum == 0.0
sum.addFunction(x2); // sum == x^2
sum.addFunction(gauss); // sum == x^2+e^{-x^2}
sum(2.0); // == 4 + e^-4
CompoundParam[0] = 2.0; // sum ==2x^2+e^{-x^2}
sum(2.0); // == 8 + e^-4
Template Type Argument Requirements (T)
- T should have standard numerical operators and exp() function. Current implementation only tested for real types.
- To obtain derivatives, the derivatives should be defined.
Thrown Exceptions
- AipsError if dimensions of functions added different
Motivation
This class was created to allow a non-linear least squares fitter to fit a (potentially) arbitrary number of functions (typically Gaussians).
To Do
- Nothing I know of
Member Description
CompoundFunction() : CompoundParam<T>()
The default constructor -- no functions, no parameters, nothing, the function operator returns a 0.
CompoundFunction(const CompoundFunction<T> &other) : other<T>(other)
CompoundFunction(const CompoundFunction<T> &other, Bool) : other<T>(other, True)
template <class W> CompoundFunction(const CompoundFunction<W> &other) : CompoundParam<T>(other)
template <class W> CompoundFunction(const CompoundFunction<W> &other, Bool) : CompoundParam<T>(other, True)
Make this object a (deep) copy of other. If parameters have been set
without an intervening calculation, a consolidate() could
be necessary on other first.
CompoundFunction<T> &operator=(const CompoundFunction<T> &other)
Make this object a (deep) copy of other.virtual ~CompoundFunction()
Destructorvirtual T eval(typename Function<T>::FunctionArg x) const
Evaluate the function at x.CompoundFunction<T> &consolidate()
Consolidate the parameter settings. This could be necessary if parameters have been set, and a copy constructor called. This is necessary before and after the setting of local parameters; i.e. the parameters of the individual functions.
virtual Function<T> *clone() const
virtual Function<typename FunctionTraits<T>::DiffType> *cloneAD() const
virtual Function<typename FunctionTraits<T>::BaseType> *cloneNonAD() const
Return a copy of this object from the heap. The caller is responsible for
deleting the pointer.
void fromParam_p() const
Copy the local parameters from general blockvoid toParam_p()
Make the general block from local parameterstemplate <class T> class CompoundFunction_PS<AutoDiff<T> > :public CompoundParam<AutoDiff<T> >
Interface
- CompoundFunction_PS() : CompoundParam<AutoDiff<T> >()
- CompoundFunction_PS(const CompoundFunction_PS<AutoDiff<T> > &other) : other<AutoDiff<T> >(other)
- template <class W> CompoundFunction_PS(const CompoundFunction_PS<W> &other) : CompoundParam<other<T> >(other)
- CompoundFunction_PS<AutoDiff<T> > & operator=(const CompoundFunction_PS<AutoDiff<T> > &other)
- virtual ~CompoundFunction_PS()
- virtual AutoDiff<T> eval(typename Function<AutoDiff<T> >::FunctionArg x) const
- uInt addFunction(const Function<AutoDiff<T> > &newFunction)
- CompoundFunction_PS<AutoDiff<T> > &consolidate()
- virtual Function<AutoDiff<T> > *clone() const
- virtual Function<typename FunctionTraits<Traits<T> >::DiffType> *cloneAD() const
- virtual Function<typename FunctionTraits<Traits<T> >::BaseType> *cloneNonAD() const
- CompoundFunction_PS(const CompoundFunction_PS<AutoDiff<T> > &other) : other<AutoDiff<T> >(other)
- void fromParam_p() const
- void toParam_p()
Description
Synopsis
The name CompoundFunction_PS is only for cxx2html documentation problems. Use CompoundFunction in your code.
Member Description
CompoundFunction_PS() : CompoundParam<AutoDiff<T> >()
The default constructor -- no functions, no parameters, nothing, the function operator returns a 0.
CompoundFunction_PS(const CompoundFunction_PS<AutoDiff<T> > &other) : other<AutoDiff<T> >(other)
template <class W> CompoundFunction_PS(const CompoundFunction_PS<W> &other) : CompoundParam<other<T> >(other)
Make this object a (deep) copy of other. If parameters have been set
without an intervening calculation, a consolidate() could
be necessary on other first.
CompoundFunction_PS<AutoDiff<T> > & operator=(const CompoundFunction_PS<AutoDiff<T> > &other)
Make this object a (deep) copy of other.virtual ~CompoundFunction_PS()
Destructorvirtual AutoDiff<T> eval(typename Function<AutoDiff<T> >::FunctionArg x) const
Evaluate the function and its derivatives at x wrt to the coefficients.uInt addFunction(const Function<AutoDiff<T> > &newFunction)
Add a function to the sum. All functions must have the same ndim() as the first one. Returns the (zero relative) number of the function just added.