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mlpack/fastlib/trilinos/include/Teuchos_PolynomialDecl.hpp
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// @HEADER
// ***********************************************************************
//
// Teuchos: Common Tools Package
// Copyright (2004) Sandia Corporation
//
// Under terms of Contract DE-AC04-94AL85000, there is a non-exclusive
// license for use of this work by or on behalf of the U.S. Government.
//
// This library is free software; you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as
// published by the Free Software Foundation; either version 2.1 of the
// License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
// USA
// Questions? Contact Michael A. Heroux (maherou@sandia.gov)
//
// ***********************************************************************
// @HEADER
#ifndef TEUCHOS_POLYNOMIAL_DECL_HPP
#define TEUCHOS_POLYNOMIAL_DECL_HPP
#include "Teuchos_Describable.hpp"
#include "Teuchos_RCP.hpp"
#include "Teuchos_PolynomialTraits.hpp"
namespace Teuchos {
//! Lightweight container class to represent a simple polynomial.
/*!
* This class represents a simple polynomial of the form:
* \f[
* x(t) = \sum_{i=0}^d x_i t^i
* \f]
* where \f$d\f$ is the degree of the polynomial and \f$t\f$ is a scalar.
* The coefficients \f$x_i\f$, \f$i=0,\dots,d\f$ can be scalars, vectors,
* operators, etc., any type that can implement Teuchos::PolynomialTraits.
* A template specialization of Teuchos::PolynomialTraits must be provided
* for the coefficient type, however Teuchos::PolynomailTraits does provide
* a default template definition for scalars.
*
* This class provides methods for creating a polynomial of some degree,
* setting and retreiving coefficients, and evaluating the polynomial and
* its derivative at some value \f$t\f$.
*/
template <typename CoeffT>
class Polynomial : virtual public Teuchos::Describable {
public:
//! Typename of coefficients
typedef CoeffT coeff_type;
//! Typename of scalars
typedef typename Teuchos::PolynomialTraits<coeff_type>::scalar_type scalar_type;
//! Create a polynomial of degree \c deg
/*!
* If \c reserve > \c deg, a polynomial of degree \c deg will be created,
* but space for \c reserve + 1 coefficients will be created to allow
* future increases in the degree of the polynomial to be more efficient.
* A clone of \c cloneCoeff will be placed at each coefficient.
*/
Polynomial(unsigned int deg, const CoeffT& cloneCoeff,
unsigned int reserve = 0);
//! Create a polynomial of degree \c deg without cloning. DANGEROUS!
/*!
* In this version of the constructor, no clone object is provided,
* and therefore no storage will be created for each coefficient.
* In this case, setCoefficientPtr() below should be used to set
* each coefficient pointer to a valid cofficient. This constructor exists
* to be able to create an efficient "view" of another polynomial.
*/
Polynomial(unsigned int deg, unsigned int reserve = 0);
//! Destructor
~Polynomial();
//! Return degree of polynomial
unsigned int degree() const { return d; }
//! Set degree of polynomial to \c deg
void setDegree(unsigned int deg);
//! Return ref-count pointer to coefficient \c i
Teuchos::RCP<CoeffT>
getCoefficient(unsigned int i);
//! Return ref-count pointer to constant coefficient \c i
Teuchos::RCP<const CoeffT>
getCoefficient(unsigned int i) const;
//! Set coefficient \c i to \c c
void setCoefficient(unsigned int i, const CoeffT& v);
//! Set pointer for coefficient \c i to \c c_ptr. DANGEROUS!
/*!
* Directly set the coefficient pointer to c_ptr. This method should
* be used with care since future calls to setCoefficient(i,c) will
* also modify the coefficient pointed to \c c_ptr. However, in certain
* situations it is necessary to do this for efficiency.
*/
void setCoefficientPtr(unsigned int i,
const Teuchos::RCP<CoeffT>& c_ptr);
//! Evaluate polynomial and possibly its derivative at time \c t
/*!
* The value of the polynomial at \c t is computed and stored in \c *x.
* If \c xdot is not \c NULL, the derivative with respect to t is
* evaluated and stored in \c *xdot.
*
* Horner's method is used to efficiently evaluate the polynomial
* and its derivative.
*/
void evaluate(typename Teuchos::Polynomial<CoeffT>::scalar_type t,
CoeffT* x, CoeffT* xdot = NULL) const;
private:
//! Prohibit copying
Polynomial(const Polynomial&);
//! Prohibit copying
Polynomial& operator=(const Polynomial&);
protected:
//! Degree of polynomial
unsigned int d;
//! Size of polynomial (may be > d)
unsigned int sz;
//! Vector of polynomial coefficients
/*!
* \c coeff[i] corresponds to the degree \c i term, \c i=0,...,d
*/
std::vector< Teuchos::RCP<CoeffT> > coeff;
}; // class Polynomial
} // end namespace Teuchos
#endif // TEUCHOS_POLYNOMIAL_DECL_HPP