/*
Author: Juan Rada-Vilela, Ph.D.
Copyright (C) 2010-2014 FuzzyLite Limited
All rights reserved
This file is part of fuzzylite.
fuzzylite is free software: you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License as published by the Free
Software Foundation, either version 3 of the License, or (at your option)
any later version.
fuzzylite 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 Lesser General Public License
for more details.
You should have received a copy of the GNU Lesser General Public License
along with fuzzylite. If not, see .
fuzzyliteâ„¢ is a trademark of FuzzyLite Limited.
*/
#include "fl/term/Concave.h"
namespace fl {
Concave::Concave(const std::string& name, scalar inflection, scalar end, scalar height)
: Term(name, height), _inflection(inflection), _end(end) {
}
Concave::~Concave() {
}
std::string Concave::className() const {
return "Concave";
}
scalar Concave::membership(scalar x) const {
if (fl::Op::isNaN(x)) return fl::nan;
if (fl::Op::isLE(_inflection, _end)) { //Concave increasing
if (fl::Op::isLt(x, _end)) {
return _height * (_end - _inflection) / (2 * _end - _inflection - x);
}
} else { //Concave decreasing
if (fl::Op::isGt(x, _end)) {
return _height * (_inflection - _end) / (_inflection - 2 * _end + x);
}
}
return _height * 1.0;
}
std::string Concave::parameters() const {
return Op::join(2, " ", _inflection, _end) +
(not Op::isEq(_height, 1.0) ? " " + Op::str(_height) : "");
}
void Concave::configure(const std::string& parameters) {
if (parameters.empty()) return;
std::vector values = Op::split(parameters, " ");
std::size_t required = 2;
if (values.size() < required) {
std::ostringstream ex;
ex << "[configuration error] term <" << className() << ">"
<< " requires <" << required << "> parameters";
throw fl::Exception(ex.str(), FL_AT);
}
setInflection(Op::toScalar(values.at(0)));
setEnd(Op::toScalar(values.at(1)));
if (values.size() > required)
setHeight(Op::toScalar(values.at(required)));
}
void Concave::setInflection(scalar start) {
this->_inflection = start;
}
scalar Concave::getInflection() const {
return this->_inflection;
}
void Concave::setEnd(scalar end) {
this->_end = end;
}
scalar Concave::getEnd() const {
return this->_end;
}
Concave* Concave::clone() const {
return new Concave(*this);
}
Term* Concave::constructor() {
return new Concave;
}
}