/**
* @file
* $Revision: 1.1.1.1 $
* $Date: 2006/10/31 23:18:06 $
*
* Unless noted otherwise, the portions of Isis written by the USGS are
* public domain. See individual third-party library and package descriptions
* for intellectual property information, user agreements, and related
* information.
*
* Although Isis has been used by the USGS, no warranty, expressed or
* implied, is made by the USGS as to the accuracy and functioning of such
* software and related material nor shall the fact of distribution
* constitute any such warranty, and no responsibility is assumed by the
* USGS in connection therewith.
*
* For additional information, launch
* $ISISROOT/doc//documents/Disclaimers/Disclaimers.html
* in a browser or see the Privacy & Disclaimers page on the Isis website,
* http://isis.astrogeology.usgs.gov, and the USGS privacy and disclaimers on
* http://www.usgs.gov/privacy.html.
*/
#ifndef BasisFunction_h
#define BasisFunction_h
#include
#include
#include
namespace Isis {
/**
* @brief Generic linear equation class
*
* This is a base class for generating "generic" equations for the
* Isis least squares fitting algorithm (IsisLSQ). It allows the programmer
* to set up equations in the form of:
* @f[
* x = C1*T1 + C2*T2 + ... + CN*TN;
* @f]
* where C1-CN are coefficients and T1-TN are terms. Note that terms can
* be comprised of multiple variables and/or functions. For example,
* @f[
* x = C1 + C2*y + C3*y**2;
* @f]
* @f[
* x = C1 + C2*y + C3*z + C4*y*z;
* @f]
* By deriving different functions off of this base class this allows the
* least squares class to be generalized.
*
* @ingroup Math
*
* @author 2004-06-24 Jeff Anderson
*
* @internal
* @todo Add coded example
* @history 2005-03-16 Leah Dahmer modified file to support Doxygen
* documentation.
*/
class BasisFunction {
public:
BasisFunction(const QString &name, int numVars, int numCoefs);
//! Destroys the BasisFunction object.
virtual ~BasisFunction() {};
void SetCoefficients(const std::vector &coefs);
double Evaluate(const std::vector &vars);
virtual void Expand(const std::vector &vars);
/**
* Returns the number of coefficients for the equation.
*
* @return The number of coefficients.
*/
int Coefficients() const {
return p_numCoefs;
};
/**
* Returns the number of variables in the equation.
*
* @return The number of variables.
*/
int Variables() const {
return p_numVars;
};
/**
* Returns the name of the equation.
*
* @return The name of the equation.
*/
QString Name() const {
return p_name;
};
/**
* Returns the cth term. This is only valid after a Evalute/Expand has been
* invoked. It represents the expansion of the variables into the ith term.
* For example,
* @f[
* x = C1 + C2*x + C3*y + C4*x*y
* @f]
* would return x*y for the 3rd
* term (zero-based)
*
* @param c The index for the desired coefficient.
*
* @return The cth term.
*/
double Term(int c) const {
return p_terms[c];
};
/**
* Returns the ith coefficient
*
* @param i The index for the desired coefficient.
*
* @return The ith coefficient
*/
double Coefficient(int i) const {
return p_coefs[i];
};
protected:
//! The name of the equation. Call it by using Name()
QString p_name;
//! The number of variables in the equation. Call it by using Variables()
int p_numVars;
/** The number of coefficients in the equation. Call it by using
* Coefficients()
*/
int p_numCoefs;
/** A vector of the coefficients in the equation. Call it by using
* Coefficient()
*/
std::vector p_coefs;
/** A vector of the terms in the equation. Call it by using
* Term()
*/
std::vector p_terms;
};
};
#endif