parameter/LogarithmicParameterAdaptation.cpp

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#include "LogarithmicParameterAdaptation.h"
#include "Utility.h"
#include <math.h>

#define base CLinearParameterAdaptation

// M_E is the base of the natural logarithm for 'e' from math.h
CLogarithmicParameterAdaptation::CLogarithmicParameterAdaptation() : base("Logarithmic"),
    _dLogarithmBase(M_E), _dFloorValue(-INFINITY)
{
}

// Element properties
void CLogarithmicParameterAdaptation::showProperties(std::string& strResult) const
{
    base::showProperties(strResult);

    strResult += " - LogarithmBase: ";
    strResult += CUtility::toString(_dLogarithmBase);
    strResult += "\n";
    strResult += " - FloorValue: ";
    strResult += CUtility::toString(_dFloorValue);
    strResult += "\n";
}

bool CLogarithmicParameterAdaptation::fromXml(const CXmlElement& xmlElement,
                                            CXmlSerializingContext& serializingContext)
{

    if (xmlElement.hasAttribute("LogarithmBase")) {

        _dLogarithmBase = xmlElement.getAttributeDouble("LogarithmBase");

        // Avoid negative and 1 values
        if (_dLogarithmBase <= 0 || _dLogarithmBase == 1) {
            serializingContext.setError("LogarithmBase attribute cannot be negative or 1 on element"
                                        + xmlElement.getPath());

            return false;
        }
    }

    if (xmlElement.hasAttribute("FloorValue")) {
        _dFloorValue = xmlElement.getAttributeDouble("FloorValue");
    }
    // Base
    return base::fromXml(xmlElement, serializingContext);
}


int64_t CLogarithmicParameterAdaptation::fromUserValue(double dValue) const
{
    return fmax(round(base::fromUserValue(log(dValue) / log(_dLogarithmBase))),
                        _dFloorValue);
}

double CLogarithmicParameterAdaptation::toUserValue(int64_t iValue) const
{
    return exp(base::toUserValue(iValue) * log(_dLogarithmBase));
}