diff options
Diffstat (limited to 'fuzzylite/src/term/Sigmoid.cpp')
| -rw-r--r-- | fuzzylite/src/term/Sigmoid.cpp | 78 |
1 files changed, 52 insertions, 26 deletions
diff --git a/fuzzylite/src/term/Sigmoid.cpp b/fuzzylite/src/term/Sigmoid.cpp index 77d7f82..fcf165e 100644 --- a/fuzzylite/src/term/Sigmoid.cpp +++ b/fuzzylite/src/term/Sigmoid.cpp @@ -1,25 +1,17 @@ /* - Author: Juan Rada-Vilela, Ph.D. - Copyright (C) 2010-2014 FuzzyLite Limited - All rights reserved + fuzzylite (R), a fuzzy logic control library in C++. + Copyright (C) 2010-2017 FuzzyLite Limited. All rights reserved. + Author: Juan Rada-Vilela, Ph.D. <jcrada@fuzzylite.com> 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. + the terms of the FuzzyLite License included with the software. - 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 <http://www.gnu.org/licenses/>. - - fuzzylite™ is a trademark of FuzzyLite Limited. + You should have received a copy of the FuzzyLite License along with + fuzzylite. If not, see <http://www.fuzzylite.com/license/>. + fuzzylite is a registered trademark of FuzzyLite Limited. */ #include "fl/term/Sigmoid.h" @@ -27,24 +19,58 @@ namespace fl { Sigmoid::Sigmoid(const std::string& name, scalar inflection, scalar slope, scalar height) - : Term(name, height), _inflection(inflection), _slope(slope) { - } + : Term(name, height), _inflection(inflection), _slope(slope) { } - Sigmoid::~Sigmoid() { - } + Sigmoid::~Sigmoid() { } std::string Sigmoid::className() const { return "Sigmoid"; } + Complexity Sigmoid::complexity() const { + return Complexity().comparison(1).arithmetic(1 + 4).function(1); + } + scalar Sigmoid::membership(scalar x) const { - if (fl::Op::isNaN(x)) return fl::nan; - return _height * 1.0 / (1.0 + std::exp(-_slope * (x - _inflection))); + if (Op::isNaN(x)) return fl::nan; + return Term::_height * 1.0 / (1.0 + std::exp(-_slope * (x - _inflection))); + } + + scalar Sigmoid::tsukamoto(scalar activationDegree, + scalar minimum, scalar maximum) const { + + scalar w = activationDegree; + scalar z = fl::nan; + + if (Op::isEq(w, 1.0)) { + if (Op::isGE(_slope, 0.0)) { + z = maximum; + } else { + z = minimum; + } + + } else if (Op::isEq(w, 0.0)) { + if (Op::isGE(_slope, 0.0)) { + z = minimum; + } else { + z = maximum; + } + } else { + scalar a = _slope; + scalar b = _inflection; + z = b + (std::log(1.0 / w - 1.0) / -a); + } + + return z; + } + + bool Sigmoid::isMonotonic() const { + return true; } std::string Sigmoid::parameters() const { return Op::join(2, " ", _inflection, _slope) + - (not Op::isEq(_height, 1.0) ? " " + Op::str(_height) : ""); + (not Op::isEq(getHeight(), 1.0) ? " " + Op::str(getHeight()) : ""); } void Sigmoid::configure(const std::string& parameters) { @@ -55,7 +81,7 @@ namespace fl { std::ostringstream ex; ex << "[configuration error] term <" << className() << ">" << " requires <" << required << "> parameters"; - throw fl::Exception(ex.str(), FL_AT); + throw Exception(ex.str(), FL_AT); } setInflection(Op::toScalar(values.at(0))); setSlope(Op::toScalar(values.at(1))); @@ -80,11 +106,11 @@ namespace fl { } Sigmoid::Direction Sigmoid::direction() const { - if (not fl::Op::isFinite(_slope) or fl::Op::isEq(_slope, 0.0)) return ZERO; + if (not Op::isFinite(_slope) or Op::isEq(_slope, 0.0)) return Zero; - if (fl::Op::isGt(_slope, 0.0)) return POSITIVE; + if (Op::isGt(_slope, 0.0)) return Positive; - return NEGATIVE; + return Negative; } Sigmoid* Sigmoid::clone() const { |