public void AllowsToChangeHeight()
        {
            TrapezoidalFunction func = new TrapezoidalFunction(1.0, 2.0, 1.6, 1.5, 0.5);

            Assert.AreEqual(func.GetHeight(), 0.5);
        }
        public void HeightDefaultsTo1()
        {
            TrapezoidalFunction func = new TrapezoidalFunction(1.0, 2.0, 1.6, 1.5);

            Assert.AreEqual(func.GetHeight(), 1.0);
        }