test/polynomial_test.rb in polynomials-0.1.7 vs test/polynomial_test.rb in polynomials-0.2.0

@@ -1,11 +1,16 @@
 require_relative 'test_helper'
 
+Infinity = 1.0/0
 class TestPolynomial < MiniTest::Unit::TestCase
   def test_to_s
     polynomial = Polynomial.parse('5x + 2x^2 + 20')
-    assert_equal '+ 2.0 x^2 + 5.0 x + 20.0', polynomial.to_s
+    assert_equal '2x^2 + 5x + 20', polynomial.to_s
+    polynomial = Polynomial.parse('6.5435x^234 + 5.0 + 20x')
+    assert_equal '6.5435x^234 + 20x + 5', polynomial.to_s
+    polynomial = Polynomial.parse('0x^0')
+    assert_equal "0", polynomial.to_s
   end
 
   def test_derivative_of_linear_functions
     polynomial = Polynomial.parse('5x + 2')
     assert_equal Polynomial.parse('5') ,polynomial.derivative
@@ -56,33 +61,64 @@
     assert_equal({max: Set[ -1.0/0, 1.0/0 ]}, polynomial.extrema)
   end
 
   def test_no_inflection_points
     polynomial = Polynomial.parse('1 x^4')
-    assert_equal({ left: Set[-1.0/0..+1.0/0] }, polynomial.curvature_behaviour)
+    assert_equal({ left: [-1.0/0..+1.0/0] }, polynomial.curvature_behaviour)
 
     polynomial = Polynomial.parse('-1 x^4')
-    assert_equal({ right: Set[-1.0/0..+1.0/0] }, polynomial.curvature_behaviour)
+    assert_equal({ right: [-1.0/0..+1.0/0] }, polynomial.curvature_behaviour)
 
     polynomial = Polynomial.parse('5x^2')
-    assert_equal({ left: Set[-1.0/0..+1.0/0] }, polynomial.curvature_behaviour)
+    assert_equal({ left: [-1.0/0..+1.0/0] }, polynomial.curvature_behaviour)
   end
 
   def test_no_extremums
     polynomial = Polynomial.parse('5')
     assert_equal({}, polynomial.extrema)
   end
 
-  def test_no_curve_and_no_inflection_points
+  def test_no_curvature
     polynomials = []
     polynomials << Polynomial.parse('5 x + 4')
     polynomials << Polynomial.parse('4')
     polynomials.each do |polynomial|
       assert_equal({}, polynomial.curvature_behaviour)
     end
   end
 
+  def test_local_extrema_of_derivative_leads_to_no_curvature
+    polynomial = Polynomial.parse('50x^10 - 20x^2')
+    assert_equal({}, polynomial.curvature_behaviour)
+  end
+
   def test_two_inflection_points
     polynomial = Polynomial.parse('+ 1.0 x^4 + 5.0 x^3 - 1.0 x^2 + 3.0 x + 5.0')
-    assert_equal({left:Set[-1.0/0..-2.5649778198, 0.0649778198..1.0/0], right: Set[-2.5649778198..0.0649778198] } , polynomial.curvature_behaviour)
+    assert_equal({left:[-1.0/0..-2.5649778198, 0.0649778198..1.0/0], right: [-2.5649778198..0.0649778198] } , polynomial.curvature_behaviour)
+  end
+
+  def test_three_inflection_points
+    polynomial = Polynomial.new(20,4,0,-1,-200)
+    assert_equal( {:right=>[(-1/10)..0.0], :left=>[-Infinity..(-1/10), 0.0..Infinity]}, polynomial.curvature_behaviour)
+  end
+
+
+  def test_efficient_roots_calculation
+    polynomial = Polynomial.parse('200x^2342435 + 6x^20')
+    assert_equal(Set[0.0], polynomial.roots)
+  end
+
+  def test_lt
+    polynomial = Polynomial.parse('1x^2342435 + 5x')
+    assert_euqal Term.new(5,1), polynomial.lt
+  end
+
+  def test_lt
+    polynomial = Polynomial.parse('1x^2342435 + 5x')
+    assert_equal Term.new(2342435,1), polynomial.gt
+  end
+
+  def test_initalizer
+    polynomial = Polynomial.new(5,0,2,-1)
+    assert_equal '5x^3 + 2x - 1', polynomial.to_s
   end
 end