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diff --git a/fuzzylite/fl/term/ZShape.h b/fuzzylite/fl/term/ZShape.h
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+/*
+ 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 FuzzyLite License included with the software.
+
+ 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.
+ */
+
+#ifndef FL_ZSHAPE_H
+#define FL_ZSHAPE_H
+
+#include "fl/term/Term.h"
+
+namespace fl {
+
+    /**
+      The ZShape class is an edge Term that represents the Z-shaped membership
+      function.
+
+      @image html zShape.svg
+
+      @author Juan Rada-Vilela, Ph.D.
+      @see Term
+      @see Variable
+      @since 4.0
+     */
+
+    class FL_API ZShape : public Term {
+    private:
+        scalar _start, _end;
+
+    public:
+        explicit ZShape(const std::string& name = "",
+                scalar _start = fl::nan,
+                scalar _end = fl::nan,
+                scalar _height = 1.0);
+        virtual ~ZShape() FL_IOVERRIDE;
+        FL_DEFAULT_COPY_AND_MOVE(ZShape)
+
+        virtual std::string className() const FL_IOVERRIDE;
+        /**
+          Returns the parameters of the term
+          @return `"start end [height]"`
+         */
+        virtual std::string parameters() const FL_IOVERRIDE;
+        /**
+          Configures the term with the parameters
+          @param parameters as `"start end [height]"`
+         */
+        virtual void configure(const std::string& parameters) FL_IOVERRIDE;
+
+        virtual Complexity complexity() const FL_IOVERRIDE;
+        /**
+          Computes the membership function evaluated at @f$x@f$
+          @param x
+          @return @f$  \begin{cases}
+          1h & \mbox{if $x \leq s$} \cr
+          h(1 - 2\left((x - s) / (e-s)\right)^2) & \mbox{if $x \leq 0.5(s+e)$}\cr
+          h(2 \left((x - e) / (e-s)\right)^2) & \mbox{if $x < e$}\cr
+          0h & \mbox{otherwise}
+          \end{cases}@f$
+
+          where @f$h@f$ is the height of the Term,
+                @f$s@f$ is the start of the ZShape,
+                @f$e@f$ is the end of the ZShape.
+         */
+        virtual scalar membership(scalar x) const FL_IOVERRIDE;
+
+        virtual scalar tsukamoto(scalar activationDegree,
+                scalar minimum, scalar maximum) const FL_IOVERRIDE;
+
+        virtual bool isMonotonic() const FL_IOVERRIDE;
+        
+        /**
+          Sets the start of the edge
+          @param start is the start of the edge
+         */
+        virtual void setStart(scalar start);
+        /**
+          Gets the start of the edge
+          @return the start of the edge
+         */
+        virtual scalar getStart() const;
+
+        /**
+          Sets the end of the edge
+          @param end is the end of the edge
+         */
+        virtual void setEnd(scalar end);
+        /**
+          Gets the end of the edge
+          @return the end of the edge
+         */
+        virtual scalar getEnd() const;
+
+        virtual ZShape* clone() const FL_IOVERRIDE;
+
+        static Term* constructor();
+
+    };
+}
+#endif  /* ZSHAPE_H */
+