source: trunk/external-alma/components/SpectralComponents/GaussianSpectralElement.cc@ 3006

//# SpectralElement.cc: Describes (a set of related) spectral lines
//# Copyright (C) 2001,2004
//# 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
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//# $Id: GaussianSpectralElement.cc 21451 2014-06-10 07:48:08Z gervandiepen $

//# Includes
#include <components/SpectralComponents/GaussianSpectralElement.h>

#include <casa/BasicSL/Constants.h>

#include <scimath/Functionals/Gaussian1D.h>

#include <casa/iostream.h>

namespace casa { //# NAMESPACE CASA - BEGIN

//# Constants
const Double GaussianSpectralElement::SigmaToFWHM = sqrt(8.0*C::ln2);

GaussianSpectralElement::GaussianSpectralElement()
: PCFSpectralElement(SpectralElement::GAUSSIAN, 1, 0, 2*sqrt(C::ln2)/C::pi) {
        _setFunction(
                std::tr1::shared_ptr<Gaussian1D<Double> >(
                        new Gaussian1D<Double>(1, 0, 1)
                )
        );
}


GaussianSpectralElement::GaussianSpectralElement(
        const Double ampl, const Double center, const Double sigma
) : PCFSpectralElement(SpectralElement::GAUSSIAN, ampl, center, sigma) {
        _setFunction(
                std::tr1::shared_ptr<Gaussian1D<Double> >(
                        new Gaussian1D<Double>(ampl, center, sigma*SigmaToFWHM)
                )
        );
}

GaussianSpectralElement::GaussianSpectralElement(
        const Vector<Double> &param
) : PCFSpectralElement(SpectralElement::GAUSSIAN, param) {
        std::tr1::shared_ptr<Gaussian1D<Double> >(
                new Gaussian1D<Double>(param[AMP], param[CENTER], param[WIDTH]*SigmaToFWHM)
        );
}

GaussianSpectralElement::GaussianSpectralElement(
        const GaussianSpectralElement &other
) : PCFSpectralElement(other) {}

GaussianSpectralElement::~GaussianSpectralElement() {}


SpectralElement* GaussianSpectralElement::clone() const {
        return new GaussianSpectralElement(*this);
}

Double GaussianSpectralElement::getSigma() const {
        return get()[2];
}

Double GaussianSpectralElement::getFWHM() const {
        return sigmaToFWHM(get()[WIDTH]);
}

Double GaussianSpectralElement::getSigmaErr() const {
        return getError()[WIDTH];
}

Double GaussianSpectralElement::getFWHMErr() const {
        return sigmaToFWHM(getError()[WIDTH]);
}

void GaussianSpectralElement::setSigma(Double sigma) {
        if (sigma < 0) {
                sigma *= -1;
        }
        Vector<Double> p = get();
        p[WIDTH] = sigma;
        _set(p);
        Vector<Double> err = getError();
        err[WIDTH] = 0;
        setError(err);
}

void GaussianSpectralElement::set(const Vector<Double>& v) {
        PCFSpectralElement::set(v);
        (*_getFunction())[WIDTH] = sigmaToFWHM(v[WIDTH]);
}

void GaussianSpectralElement::_set(const Vector<Double>& v) {
        PCFSpectralElement::_set(v);
        (*_getFunction())[WIDTH] = sigmaToFWHM(v[WIDTH]);
}

void GaussianSpectralElement::setFWHM(Double fwhm) {
        setSigma(sigmaFromFWHM(fwhm));
}

void GaussianSpectralElement::fixSigma(const Bool isFixed) {
        Vector<Bool> myFixed = fixed();
        myFixed[WIDTH] = isFixed;
        fix(myFixed);
}

Bool GaussianSpectralElement::fixedSigma() const {
        return fixed()[WIDTH];
}

Double GaussianSpectralElement::getIntegral() const {
        static const Double c = sqrt(C::pi_4/C::ln2);
        return c * getAmpl() * getFWHM();
}

Bool GaussianSpectralElement::toRecord(
        RecordInterface& out
) const {
        PCFSpectralElement::toRecord(out);
        Vector<Double> p = out.asArrayDouble("parameters");
        Vector<Double> e = out.asArrayDouble("errors");
        p[2] = getFWHM();
        out.define("parameters", p);
        e[2] = getFWHMErr();
        out.define("errors", e);
        return True;
}

ostream &operator<<(ostream &os, const GaussianSpectralElement &elem) {
        os << SpectralElement::fromType((elem.getType())) << " element: " << endl;
    os << "  Amplitude: " << elem.getAmpl() << ", " << elem.getAmplErr();
    if (elem.fixedAmpl()) os << " (fixed)";
    os << endl << "  Center:    " << elem.getCenter() << ", " << elem.getCenterErr();
    if (elem.fixedCenter()) os << " (fixed)";
    os << endl << "  Sigma:     " << elem.getSigma() << ", " << elem.getSigmaErr();
    if (elem.fixedSigma()) os << " (fixed)";
    os << endl;
    return os;
}

Double GaussianSpectralElement::sigmaToFWHM (const Double sigma) {
   return SigmaToFWHM * sigma;
}

Double GaussianSpectralElement::sigmaFromFWHM(const Double fwhm) {
  return fwhm / SigmaToFWHM;
}

} //# NAMESPACE CASA - END