casa::SparseDiffX< T > Class Template Reference

Class that computes partial derivatives by automatic differentiation. More...

#include <SparseDiffX.h>

Inheritance diagram for casa::SparseDiffX< T >:

List of all members.

Public Member Functions
	SparseDiffX ()
	Construct a constant with a value of zero.
	SparseDiffX (const T &v)
	Construct a constant with a value of v.
	SparseDiffX (const T &v, const uInt n)
	A function f(x0,x1,...,xn,...) with a value of v.
	SparseDiffX (const T &v, const uInt n, const T &der)
	A function f(x0,x1,...,xn,...) with a value of v.
	SparseDiffX (const SparseDiff< T > &other)
	Construct one from another.
	~SparseDiffX ()
SparseDiffX< T > &	operator= (const T &v)
	Assignment operator.
SparseDiffX< T > &	operator= (const pair< uInt, T > &der)
	Assignment operator.
SparseDiffX< T > &	operator= (const vector< pair< uInt, T > > &der)
	Assignment operator.
SparseDiffX< T > &	operator= (const SparseDiff< T > &other)
	Assign one to another (deep copy).

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Detailed Description

template<class T>
class casa::SparseDiffX< T >

Class that computes partial derivatives by automatic differentiation.

Intended use:

Public interface

Review Status

Reviewed By:

UNKNOWN

Date Reviewed:

before2004/08/25

Test programs:

tSparseDiff

Demo programs:

dSparseDiff

Prerequisite

• SparseDiff

Etymology

Class that computes partial derivatives by automatic differentiation, thus SparseDiff.

Synopsis

SparseDiffX is an SparseDiff . It is used to be able to distinguish between two template incarnations; e.g. to have one or more specializations, in addition to the general template version.

Example

See for an extensive example the demo program dSparseDiff. It is based on the example given in the SparseDiff class, and shows how to have both an automatic and a specific version of a function object.

        // The function, with fixed parameters a,b:
        template <class T> class f {
        public:
          T operator()(const T& x) { return a_p*a_p*a_p*b_p*b_p*x; }
          void set(const T& a, const T& b) { a_p = a; b_p = b; }
        private:
          T a_p;
          T b_p;
        };
        // The specialized function
        template <> class f<SparseDiffX<Double> > {
        public:
          T operator()(const T& x) { return a_p*a_p*a_p*b_p*b_p*x; }
          void set(const T& a, const T& b) { a_p = a; b_p = b; }
        private:
          T a_p;
          T b_p;
        };
        // Call it with different template arguments:
          SparseDiff<Double> a1(2,0), b1(3,1), x1(7);
          f<SparseDiff<Double> > f1; f1.set(a1, b1);
          cout << "Diff a,b:   " << f1(x1) << endl;
        
          f<SparseDiffX<Double> > f12; f12.set(a1, b1);
          cout << "Same....:   " << f12(x1) << endl;
     
         // Result will be:
         // Diff a,b:  (504, [756, 336])
         // Same....:  (504, [756, 336])
     
         // It needed the template instantiations definitions:
        template class f<SparseDiff<Double> >;

Motivation

The class was created to enable separate calculations of the same function.

Template Type Argument Requirements (T)

• any class that has the standard mathematical and comparisons defined

To Do

• Nothing I know

Definition at line 121 of file SparseDiffX.h.

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Constructor & Destructor Documentation

template<class T >

casa::SparseDiffX< T >::SparseDiffX

(

)

[inline]

Construct a constant with a value of zero.

Zero derivatives.

Definition at line 125 of file SparseDiffX.h.

template<class T >

casa::SparseDiffX< T >::SparseDiffX

(

const T &

v

)

[inline]

Construct a constant with a value of v.

Zero derivatives.

Definition at line 128 of file SparseDiffX.h.

template<class T >

casa::SparseDiffX< T >::SparseDiffX	(	const T &	v,
		const uInt	n
	)		[inline]

A function f(x0,x1,...,xn,...) with a value of v.

The nth derivative is one, and all others are zero.

Definition at line 132 of file SparseDiffX.h.

template<class T >

casa::SparseDiffX< T >::SparseDiffX	(	const T &	v,
		const uInt	n,
		const T &	der
	)		[inline]

A function f(x0,x1,...,xn,...) with a value of v.

The nth derivative is der, and all other derivatives are zero.

Definition at line 137 of file SparseDiffX.h.

template<class T >

casa::SparseDiffX< T >::SparseDiffX

(

const SparseDiff< T > &

other

)

[inline]

Construct one from another.

Definition at line 141 of file SparseDiffX.h.

template<class T >

casa::SparseDiffX< T >::~SparseDiffX

(

)

[inline]

Definition at line 143 of file SparseDiffX.h.

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Member Function Documentation

template<class T >

SparseDiffX<T>& casa::SparseDiffX< T >::operator=

(

const T &

v

)

[inline]

Assignment operator.

Assign a constant to variable. All derivatives are zero.

Reimplemented from casa::SparseDiff< T >.

Definition at line 147 of file SparseDiffX.h.

Referenced by casa::SparseDiffX< T >::operator=().

template<class T >

SparseDiffX<T>& casa::SparseDiffX< T >::operator=

(

const pair< uInt, T > &

der

)

[inline]

Assignment operator.

Add a gradient to variable.

Reimplemented from casa::SparseDiff< T >.

Definition at line 153 of file SparseDiffX.h.

References casa::SparseDiffX< T >::operator=().

template<class T >

SparseDiffX<T>& casa::SparseDiffX< T >::operator=

(

const vector< pair< uInt, T > > &

der

)

[inline]

Assignment operator.

Assign gradients to variable.

Reimplemented from casa::SparseDiff< T >.

Definition at line 159 of file SparseDiffX.h.

References casa::SparseDiffX< T >::operator=().

template<class T >

SparseDiffX<T>& casa::SparseDiffX< T >::operator=

(

const SparseDiff< T > &

other

)

[inline]

Assign one to another (deep copy).

Reimplemented from casa::SparseDiff< T >.

Definition at line 166 of file SparseDiffX.h.

References casa::SparseDiffX< T >::operator=().

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The documentation for this class was generated from the following file:

• casacore/scimath/Mathematics/SparseDiffX.h