//# SpectralElement.h: Describes (a set of related) spectral lines
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//# $Id: SpectralElement.h 20652 2009-07-06 05:04:32Z Malte.Marquarding $

#ifndef COMPONENTS_POWERLOGPOLYNOMIALSPECTRALELEMENT_H
#define COMPONENTS_POWERLOGPOLYNOMIALSPECTRALELEMENT_H

#include <components/SpectralComponents/CompiledSpectralElement.h>

namespace casa { //# NAMESPACE CASA - BEGIN

// <summary>
// Describes the function most often used for determining spectral index plus higher order terms:
// y = c_0 * x**( c_1 + c_2*ln(x) + c_3*ln(x)**2 + ... )
// where c_1 is the traditional spectral index (alpha).
// </summary>

// <use visibility=export>

// <reviewed reviewer="" date="yyyy/mm/dd" tests="tSpectralFit" demos="">
// </reviewed>

// <prerequisite>
//   <li> <linkto class=SpectralElement>SpectralElement</linkto> module
// </prerequisite>
//
// <etymology>
// From power law, logarithm, and polynomial and spectral line and element
// </etymology>
//
// <synopsis>
// Describes a function that can be used to fit for spectral index and higher order terms

// </synopsis>
//
// <example>
// </example>
//
// <motivation>
// To have a spectral element representing a spectral index function.
// </motivation>


class PowerLogPolynomialSpectralElement: public SpectralElement {
public:

	/*
	// Constructor. The n coefficients c_i to be solved for are
	// c_0 * nu**(c_1 + c_2*log(x) + c_3*log(x)**2 + ... + c_(n-1)*log(x)**(n - 2))
	explicit PowerLogPolynomialSpectralElement(uInt n);
*/
	// Construct with the given parameters. See above constructor for order in which the parameters should
	// be supplied.
	PowerLogPolynomialSpectralElement(const Vector<Double> &param);

	// Copy constructor (deep copy)
	PowerLogPolynomialSpectralElement(const PowerLogPolynomialSpectralElement &other);

	~PowerLogPolynomialSpectralElement();

	PowerLogPolynomialSpectralElement &operator=(
		const PowerLogPolynomialSpectralElement& other
	);

	SpectralElement* clone() const;
/*
private:
	void _makeFunction();
*/
};

ostream &operator<<(ostream& os, const PowerLogPolynomialSpectralElement& elem);


} //# NAMESPACE CASA - END

#endif