SpectralElement.h

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//# SpectralElement.h: Describes (a set of related) spectral lines
//# Copyright (C) 2001,2003,2004
//# Associated Universities, Inc. Washington DC, USA.
//#
//# This library is free software; you can redistribute it and/or modify it
//# under the terms of the GNU Library General Public License as published by
//# the Free Software Foundation; either version 2 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 Library General Public
//# License for more details.
//#
//# You should have received a copy of the GNU Library General Public License
//# along with this library; if not, write to the Free Software Foundation,
//# Inc., 675 Massachusetts Ave, Cambridge, MA 02139, USA.
//#
//# Correspondence concerning AIPS++ should be addressed as follows:
//#        Internet email: aips2-request@nrao.edu.
//#        Postal address: AIPS++ Project Office
//#                        National Radio Astronomy Observatory
//#                        520 Edgemont Road
//#                        Charlottesville, VA 22903-2475 USA
//#
//#
//# $Id: SpectralElement.h 20652 2009-07-06 05:04:32Z Malte.Marquarding $

#ifndef COMPONENTS_SPECTRALELEMENT_H
#define COMPONENTS_SPECTRALELEMENT_H

#include <casa/aips.h>
#include <casa/Arrays/Vector.h>
#include <casa/Containers/RecordInterface.h>

namespace casa { //# NAMESPACE CASA - BEGIN

// <summary>
// Describes (a set of related) spectral lines
// </summary>

// <use visibility=export>

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

// <prerequisite>
//   <li> <linkto module=Functionals>Functionals</linkto> module
// </prerequisite>
//
// <etymology>
// From spectral line and element
// </etymology>
//
// <synopsis>
// The SpectralElement class is the abstract base class for classes
// describing spectral components (Gaussian, Polynonomial, etc).
//
// The element can be used in the
// <linkto class=SpectralFit>SpectralFit</linkto> class and in the
// <linkto class=SpectralEstimate>SpectralEstimate</linkto> class.
//
// </synopsis>
//
// <example>
// </example>
//
// <motivation>
// To have a container for fitting of spectral profiles to an observed spectrum
// </motivation>
//
// <todo asof="2001/02/04">
//   <li> add more profile types
// </todo>

class SpectralElement { // : public RecordTransformable {
public:

        //# Enumerations
        // Types of spectral lines known
        enum Types {
                // A gaussian profile
                GAUSSIAN,
                // A polynomial baseline
                POLYNOMIAL,
                // Any compiled string functional
                COMPILED,
                // Gaussian multiplet
                GMULTIPLET,
                // Lorentzian
                LORENTZIAN,
                N_Types
        };

        virtual ~SpectralElement();

        virtual SpectralElement* clone() const = 0;

        // Evaluate the value of the element at x
        virtual Double operator()(const Double x) const = 0;

        virtual Bool operator==(const SpectralElement& other) const;

        // Get parameter n
        // <thrown>
        //  <li> AipsError if illegal n
        // </thrown>
        virtual Double operator[](const uInt n) const;

        // Get all the types available as String and codes, and number available
        static const String* allTypes(Int &nall,
                        const SpectralElement::Types *&typ);
        // Get a string from the type
        static const String &fromType(SpectralElement::Types tp);
        // Get a type from a (non-case sensitive; minimum match) String
        static Bool toType(SpectralElement::Types &tp,
                        const String &typName);

        // Get the data for this element
        // <thrown>
        //  <li> AipsError if element does not have data
        //         (e.g. amplitude for POLYNOMIAL)
        // </thrown>
        // <group>
        // Get type of this element
        SpectralElement::Types getType() const { return tp_p; }

        // Get all parameters
        void get(Vector<Double>& params) const;

        Vector<Double> get() const;

        // Get error estimates of parameters
        void getError(Vector<Double> &err) const;
        Vector<Double> getError() const;

        // Get the order (i.e. the number of parameters)
        uInt getOrder() const { return par_p.nelements(); };

        // Set the error fields
        virtual void setError(const Vector<Double> &err);

        // Set fixed parameters (True) or unset them (False)
        // <thrown>
        //   <li> AipsError if incorrect number of parameters (e.g. not 3 for GAUSSIAN)
        // </thrown>

        // Fix/unfix all in one go
        virtual void fix(const Vector<Bool>& fix);

        // Get the fix state[s]
        const Vector<Bool> &fixed() const;

        // Save to a record.
        virtual Bool toRecord(RecordInterface& out) const;

        // set parameters
        virtual void set(const Vector<Double>& params);

protected:
        SpectralElement() {}

        SpectralElement(const SpectralElement& other);

        SpectralElement &operator=(const SpectralElement& other);

        void _construct(const Types type, const Vector<Double>& params);

        void _set(const Vector<Double>& params);

        void _setType(const Types type);

private:
        //#Data
        // type of element
        Types tp_p;

        // The parameters of the function. I.e. the polynomial coefficients;
        // amplitude, center and sigma of a Gaussian.
        Vector<Double> par_p;
        // The errors of the parameters
        Vector<Double> err_p;
        // The indication if the parameter has to be fixed (True) or solved (False).
        // Solved is the default.
        Vector<Bool> fix_p;

};

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

Bool near(const SpectralElement& s1, const SpectralElement& s2, const Double tol);

Bool nearAbs(const SpectralElement& s1, const SpectralElement& s2, const Double tol);


} //# NAMESPACE CASA - END

#endif