tests/test_linear.py

   1 import unittest
   2
   3 from fractions import Fraction
   4
   5 from pypol.linear import *
   6
   7
   8 class TestExpression(unittest.TestCase):
   9
  10     def setUp(self):
  11         self.x = Expression({'x': 1})
  12         self.y = Expression({'y': 1})
  13         self.z = Expression({'z': 1})
  14         self.zero = Expression(constant=0)
  15         self.one = Expression(constant=1)
  16         self.pi = Expression(constant=Fraction(22, 7))
  17         self.expr = self.x - 2*self.y + 3
  18
  19     def test_new_subclass(self):
  20         self.assertIsInstance(self.x, Symbol)
  21         self.assertIsInstance(self.pi, Constant)
  22         self.assertNotIsInstance(self.x + self.pi, Symbol)
  23         self.assertNotIsInstance(self.x + self.pi, Constant)
  24         xx = Expression({'x': 2})
  25         self.assertNotIsInstance(xx, Symbol)
  26
  27     def test_new_types(self):
  28         with self.assertRaises(TypeError):
  29             Expression('x + y', 2)
  30         self.assertEqual(Expression({'x': 2}), Expression({self.x: 2}))
  31         with self.assertRaises(TypeError):
  32             Expression({0: 2})
  33         with self.assertRaises(TypeError):
  34             Expression({'x': '2'})
  35         self.assertEqual(Expression(constant=1), Expression(constant=self.one))
  36         with self.assertRaises(TypeError):
  37             Expression(constant='1')
  38
  39     def test_symbols(self):
  40         self.assertCountEqual(self.x.symbols, ['x'])
  41         self.assertCountEqual(self.pi.symbols, [])
  42         self.assertCountEqual(self.expr.symbols, ['x', 'y'])
  43
  44     def test_dimension(self):
  45         self.assertEqual(self.x.dimension, 1)
  46         self.assertEqual(self.pi.dimension, 0)
  47         self.assertEqual(self.expr.dimension, 2)
  48
  49     def test_coefficient(self):
  50         self.assertEqual(self.expr.coefficient('x'), 1)
  51         self.assertEqual(self.expr.coefficient('y'), -2)
  52         self.assertEqual(self.expr.coefficient(self.y), -2)
  53         self.assertEqual(self.expr.coefficient('z'), 0)
  54         with self.assertRaises(TypeError):
  55             self.expr.coefficient(0)
  56         with self.assertRaises(TypeError):
  57             self.expr.coefficient(self.expr)
  58
  59     def test_getitem(self):
  60         self.assertEqual(self.expr['x'], 1)
  61         self.assertEqual(self.expr['y'], -2)
  62         self.assertEqual(self.expr[self.y], -2)
  63         self.assertEqual(self.expr['z'], 0)
  64         with self.assertRaises(TypeError):
  65             self.expr[0]
  66         with self.assertRaises(TypeError):
  67             self.expr[self.expr]
  68
  69     def test_coefficients(self):
  70         self.assertCountEqual(self.expr.coefficients(), [('x', 1), ('y', -2)])
  71
  72     def test_constant(self):
  73         self.assertEqual(self.x.constant, 0)
  74         self.assertEqual(self.pi.constant, Fraction(22, 7))
  75         self.assertEqual(self.expr.constant, 3)
  76
  77     def test_isconstant(self):
  78         self.assertFalse(self.x.isconstant())
  79         self.assertTrue(self.pi.isconstant())
  80         self.assertFalse(self.expr.isconstant())
  81
  82     def test_values(self):
  83         self.assertCountEqual(self.expr.values(), [1, -2, 3])
  84
  85     def test_issymbol(self):
  86         self.assertTrue(self.x.issymbol())
  87         self.assertFalse(self.pi.issymbol())
  88         self.assertFalse(self.expr.issymbol())
  89
  90     def test_bool(self):
  91         self.assertTrue(self.x)
  92         self.assertFalse(self.zero)
  93         self.assertTrue(self.pi)
  94         self.assertTrue(self.expr)
  95
  96     def test_pos(self):
  97         self.assertEqual(+self.expr, self.expr)
  98
  99     def test_neg(self):
 100         self.assertEqual(-self.expr, -self.x + 2*self.y - 3)
 101
 102     def test_add(self):
 103         self.assertEqual(self.x + Fraction(22, 7), self.x + self.pi)
 104         self.assertEqual(Fraction(22, 7) + self.x, self.x + self.pi)
 105         self.assertEqual(self.x + self.x, 2 * self.x)
 106         self.assertEqual(self.expr + 2*self.y, self.x + 3)
 107
 108     def test_sub(self):
 109         self.assertEqual(self.x - self.x, 0)
 110         self.assertEqual(self.expr - 3, self.x - 2*self.y)
 111         self.assertEqual(0 - self.x, -self.x)
 112
 113     def test_mul(self):
 114         self.assertEqual(self.pi * 7, 22)
 115         self.assertEqual(self.expr * 0, 0)
 116         self.assertEqual(0 * self.expr, 0)
 117         self.assertEqual(self.expr * 2, 2*self.x - 4*self.y + 6)
 118
 119     def test_div(self):
 120         with self.assertRaises(ZeroDivisionError):
 121             self.expr / 0
 122         self.assertEqual(self.expr / 2, self.x / 2 - self.y + Fraction(3, 2))
 123
 124     def test_str(self):
 125         self.assertEqual(str(Expression()), '0')
 126         self.assertEqual(str(self.x), 'x')
 127         self.assertEqual(str(-self.x), '-x')
 128         self.assertEqual(str(self.pi), '22/7')
 129         self.assertEqual(str(self.expr), 'x - 2*y + 3')
 130
 131     def test_repr(self):
 132         self.assertEqual(repr(self.x), "Symbol('x')")
 133         self.assertEqual(repr(self.one), 'Constant(1)')
 134         self.assertEqual(repr(self.expr), "Expression({'x': 1, 'y': -2}, 3)")
 135
 136     @unittest.expectedFailure
 137     def test_fromstring(self):
 138         self.assertEqual(Expression.fromstring('x'), self.x)
 139         self.assertEqual(Expression.fromstring('-x'), -self.x)
 140         self.assertEqual(Expression.fromstring('22/7'), self.pi)
 141         self.assertEqual(Expression.fromstring('x - 2y + 3'), self.expr)
 142         self.assertEqual(Expression.fromstring('x - (3-1)y + 3'), self.expr)
 143         self.assertEqual(Expression.fromstring('x - 2*y + 3'), self.expr)
 144
 145     def test_eq(self):
 146         self.assertEqual(self.expr, self.expr)
 147         self.assertNotEqual(self.x, self.y)
 148         self.assertEqual(self.zero, 0)
 149
 150     def test__toint(self):
 151         self.assertEqual((self.x + self.y/2 + self.z/3)._toint(),
 152                 6*self.x + 3*self.y + 2*self.z)
 153
 154
 155 class TestConstant(unittest.TestCase):
 156
 157     pass
 158
 159
 160 class TestSymbol(unittest.TestCase):
 161
 162     def setUp(self):
 163         self.x = Symbol('x')
 164         self.y = Symbol('y')
 165
 166     def test_name(self):
 167         self.assertEqual(self.x.name, 'x')
 168
 169     def test_symbols(self):
 170         self.assertListEqual(list(symbols('x y')), [self.x, self.y])
 171         self.assertListEqual(list(symbols('x,y')), [self.x, self.y])
 172         self.assertListEqual(list(symbols(['x', 'y'])), [self.x, self.y])
 173
 174
 175 class TestOperators(unittest.TestCase):
 176
 177     pass
 178
 179
 180 class TestPolyhedron(unittest.TestCase):
 181
 182     pass