class FuzzySet {

	private int shape; // 1:triangle;  2:trapezium; 3:isosceles trapezium
	private double tri[];
	private double trapz[];
	private double isotrapz[];

	public FuzzySet(int shape, double[] pts) {
		this.shape = shape;
		if(shape==1 && pts.length==3) {
			tri = pts;
		}
		else if(shape==2 && pts.length==2) {
			trapz = pts;
		}
		else if(shape==3 && pts.length==4) {
			isotrapz = pts;
		}
		else System.err.println("shape points does not match");
	}
	
	public double getTriMembership(double x) {
		
		if( x>=0 && x<tri[0]) {
			return 0.0;
		}
		else if( x>=tri[0] && x<tri[1]) {
			return (x-tri[0])/(tri[1]-tri[0]);
		}
		else if( x>=tri[1] && x<tri[2]) {
			return 1.0 - (x-tri[1])/(tri[2]-tri[1]);
		}
		else {
			return 0.0;
		}
	}
	
	public double getTrapzMembership(boolean left, double x) { //true->left; false->right
		
		if( x>=0.0 && x<trapz[0]) {
			if(left) return 1.0;
			return 0.0;
		}
		else if( x>=trapz[0] && x<trapz[1]) {
			double tmp = (x-trapz[0])/(trapz[1]-trapz[0]);
			if(left) return 1.0 - tmp;
			return tmp;
		}
		else {
			if(left) return 0.0;
			return 1.0;
		}
	}
	
	public double getIsoTrapzMembership(double x) {
		
		if( x>=isotrapz[0] && x<isotrapz[1]) {
			return (x-isotrapz[0])/(isotrapz[1]-isotrapz[0]);
		}
		if( x>=isotrapz[1] && x<isotrapz[2]) {
			return 1.0;
		}
		if( x>=isotrapz[2] && x<isotrapz[3]) {
			return 1.0 - (x-isotrapz[2])/(isotrapz[3]-isotrapz[2]);
		}
		else return 0.0;
	}
			
	
}