src/bigint_presentation_code/test_matrix.py

   1 import unittest
   2 from fractions import Fraction
   3
   4 from bigint_presentation_code.matrix import Matrix
   5
   6
   7 class TestMatrix(unittest.TestCase):
   8     def test_repr(self):
   9         self.assertEqual(repr(Matrix(2, 3, [0, 1, 2,
  10                                             3, 4, 5])),
  11                          'Matrix(height=2, width=3, data=[\n'
  12                          '    0, 1, 2,\n'
  13                          '    3, 4, 5,\n'
  14                          '])')
  15         self.assertEqual(repr(Matrix(2, 3, [0, 1, Fraction(2) / 3,
  16                                             3, 4, 5])),
  17                          'Matrix(height=2, width=3, data=[\n'
  18                          '    0, 1, Fraction(2, 3),\n'
  19                          '    3, 4, 5,\n'
  20                          '])')
  21         self.assertEqual(repr(Matrix(0, 3)), 'Matrix(height=0, width=3)')
  22         self.assertEqual(repr(Matrix(2, 0)), 'Matrix(height=2, width=0)')
  23
  24     def test_eq(self):
  25         self.assertFalse(Matrix(1, 1) == 5)
  26         self.assertFalse(5 == Matrix(1, 1))
  27         self.assertFalse(Matrix(2, 1) == Matrix(1, 1))
  28         self.assertFalse(Matrix(1, 2) == Matrix(1, 1))
  29         self.assertTrue(Matrix(1, 1) == Matrix(1, 1))
  30         self.assertTrue(Matrix(1, 1, [1]) == Matrix(1, 1, [1]))
  31         self.assertFalse(Matrix(1, 1, [2]) == Matrix(1, 1, [1]))
  32
  33     def test_add(self):
  34         self.assertEqual(Matrix(2, 2, [1, 2, 3, 4])
  35                          + Matrix(2, 2, [40, 30, 20, 10]),
  36                          Matrix(2, 2, [41, 32, 23, 14]))
  37
  38     def test_identity(self):
  39         self.assertEqual(Matrix.identity(2, 2),
  40                          Matrix(2, 2, [1, 0,
  41                                        0, 1]))
  42         self.assertEqual(Matrix.identity(1, 3),
  43                          Matrix(1, 3, [1, 0, 0]))
  44         self.assertEqual(Matrix.identity(2, 3),
  45                          Matrix(2, 3, [1, 0, 0,
  46                                        0, 1, 0]))
  47         self.assertEqual(Matrix.identity(3),
  48                          Matrix(3, 3, [1, 0, 0,
  49                                        0, 1, 0,
  50                                        0, 0, 1]))
  51
  52     def test_sub(self):
  53         self.assertEqual(Matrix(2, 2, [40, 30, 20, 10])
  54                          - Matrix(2, 2, [-1, -2, -3, -4]),
  55                          Matrix(2, 2, [41, 32, 23, 14]))
  56
  57     def test_neg(self):
  58         self.assertEqual(-Matrix(2, 2, [40, 30, 20, 10]),
  59                          Matrix(2, 2, [-40, -30, -20, -10]))
  60
  61     def test_mul(self):
  62         self.assertEqual(Matrix(2, 2, [1, 2, 3, 4]) * Fraction(3, 2),
  63                          Matrix(2, 2, [Fraction(3, 2), 3, Fraction(9, 2), 6]))
  64         self.assertEqual(Fraction(3, 2) * Matrix(2, 2, [1, 2, 3, 4]),
  65                          Matrix(2, 2, [Fraction(3, 2), 3, Fraction(9, 2), 6]))
  66
  67     def test_matmul(self):
  68         self.assertEqual(Matrix(2, 2, [1, 2, 3, 4])
  69                          @ Matrix(2, 2, [4, 3, 2, 1]),
  70                          Matrix(2, 2, [8, 5, 20, 13]))
  71         self.assertEqual(Matrix(3, 2, [6, 5, 4, 3, 2, 1])
  72                          @ Matrix(2, 1, [1, 2]),
  73                          Matrix(3, 1, [16, 10, 4]))
  74
  75     def test_inverse(self):
  76         self.assertEqual(Matrix(0, 0).inverse(), Matrix(0, 0))
  77         self.assertEqual(Matrix(1, 1, [2]).inverse(),
  78                          Matrix(1, 1, [Fraction(1, 2)]))
  79         self.assertEqual(Matrix(1, 1, [1]).inverse(),
  80                          Matrix(1, 1, [1]))
  81         self.assertEqual(Matrix(2, 2, [1, 0, 1, 1]).inverse(),
  82                          Matrix(2, 2, [1, 0, -1, 1]))
  83         self.assertEqual(Matrix(3, 3, [0, 1, 0,
  84                                        1, 0, 0,
  85                                        0, 0, 1]).inverse(),
  86                          Matrix(3, 3, [0, 1, 0,
  87                                        1, 0, 0,
  88                                        0, 0, 1]))
  89         _1_2 = Fraction(1, 2)
  90         _1_3 = Fraction(1, 3)
  91         _1_6 = Fraction(1, 6)
  92         self.assertEqual(Matrix(5, 5, [1, 0, 0, 0, 0,
  93                                        1, 1, 1, 1, 1,
  94                                        1, -1, 1, -1, 1,
  95                                        1, -2, 4, -8, 16,
  96                                        0, 0, 0, 0, 1]).inverse(),
  97                          Matrix(5, 5, [1, 0, 0, 0, 0,
  98                                        _1_2, _1_3, -1, _1_6, -2,
  99                                        -1, _1_2, _1_2, 0, -1,
 100                                        -_1_2, _1_6, _1_2, -_1_6, 2,
 101                                        0, 0, 0, 0, 1]))
 102         with self.assertRaisesRegex(ZeroDivisionError, "Matrix is singular"):
 103             Matrix(1, 1, [0]).inverse()
 104         with self.assertRaisesRegex(ZeroDivisionError, "Matrix is singular"):
 105             Matrix(2, 2, [0, 0, 1, 1]).inverse()
 106         with self.assertRaisesRegex(ZeroDivisionError, "Matrix is singular"):
 107             Matrix(2, 2, [1, 0, 1, 0]).inverse()
 108         with self.assertRaisesRegex(ZeroDivisionError, "Matrix is singular"):
 109             Matrix(2, 2, [1, 1, 1, 1]).inverse()
 110
 111
 112 if __name__ == "__main__":
 113     unittest.main()