public void Test2()
 {
     Assert.IsTrue(CalculateFunctionFx.GetFunction(new[] { 0, 3, 6, 9, 12 })(10) == 30);
 }
 public void ShouldFail()
 {
     Assert.Throws <ArgumentException>(() => { CalculateFunctionFx.GetFunction(new[] { 0, 1, 2, 3, 10 })(5); });
 }
 public void Test1()
 {
     Assert.IsTrue(CalculateFunctionFx.GetFunction(new[] { 0, 1, 2, 3, 4 })(5) == 5);
 }