added quadratic test and solution

Author: PythonCHB

Solutions/Session08/quadratic.py

@@ -0,0 +1,22 @@
+#!/usr/bin/env python
+
+"""
+quadratic function evaluator:
+
+example of callable functions
+"""
+
+
+class Quadratic(object):
+    """
+    class for evaluating the quadratic equation
+    """
+    def __init__(self, a, b, c):
+        self.a = a
+        self.b = b
+        self.c = c
+
+    def __call__(self, x):
+        return (self.a * x**2) + (self.b * x) + self.c
+
+

Solutions/Session08/test_quadratic.py

@@ -0,0 +1,26 @@
+#!/usr/bin/env python
+
+"""
+test code for the quadratic function evaluator
+"""
+
+import pytest
+
+from quadratic import Quadratic
+
+
+def test_init():
+    q = Quadratic(1,2,3)
+
+
+def test_evaluate():
+    q = Quadratic(1,2,3)
+
+    assert q(3) == 9 + 6 + 3
+
+
+def test_bad_input():
+
+    with pytest.raises(TypeError):
+        q = Quadratic(2,3)
+