test/analyzable_test.rb in polynomials-0.4.0 vs test/analyzable_test.rb in polynomials-0.4.1

@@ -71,6 +71,21 @@
     assert_equal nil, polynomial.strives_for
 
     polynomial = Polynomial.parse('+ 1.0 x^4 + 5.0 x^3 - 1.0 x^2 + 3.0 x + 5.0').derivative
     assert_equal [-Infinity,Infinity], polynomial.strives_for
   end
+
+  def test_inflection_points_some_coefficients_of_derivative2_zero
+    polynomial = Polynomial.parse('x^5 + x^1')
+    assert_set_eql Set[], polynomial.inflection_points
+  end
+
+  def test_curvature_behaviour_degree_4
+    polynomial = Polynomial.parse('x^5 + x^1')
+    assert_equal({ :right => [[-Infinity,0.0]], :left => [[0.0, Infinity]] }, polynomial.curvature_behaviour)
+  end
+
+  def test_strives_for_no_roots
+    polynomial = Polynomial.new(1,0,0,0,0)
+    assert_equal [Infinity,Infinity], polynomial.strives_for
+  end
 end