X-Git-Url: https://scm.cri.ensmp.fr/git/linpy.git/blobdiff_plain/66e41ccd173874b3309e4c24be64c7b6b2ac6298..1d494bb187b70135df721c13306d7f26fdf33f50:/pypol/tests/test_linexprs.py

diff --git a/pypol/tests/test_linexprs.py b/pypol/tests/test_linexprs.py
new file mode 100644
index 0000000..1606ea0
--- /dev/null
+++ b/pypol/tests/test_linexprs.py
@@ -0,0 +1,269 @@
+import functools
+import unittest
+
+from fractions import Fraction
+
+from ..linexprs import *
+
+
+try:
+    import sympy
+    def _requires_sympy(func):
+        @functools.wraps(func)
+        def wrapper(self):
+            return func(self)
+        return wrapper
+except ImportError:
+    def _requires_sympy(func):
+        @functools.wraps(func)
+        def wrapper(self):
+            raise unittest.SkipTest('SymPy is not available')
+        return wrapper
+
+
+class TestExpression(unittest.TestCase):
+
+    def setUp(self):
+        self.x = Expression({'x': 1})
+        self.y = Expression({'y': 1})
+        self.z = Expression({'z': 1})
+        self.zero = Expression(constant=0)
+        self.one = Expression(constant=1)
+        self.pi = Expression(constant=Fraction(22, 7))
+        self.expr = self.x - 2*self.y + 3
+
+    def test_new(self):
+        self.assertIsInstance(self.x, Symbol)
+        self.assertIsInstance(self.pi, Constant)
+        self.assertNotIsInstance(self.x + self.pi, Symbol)
+        self.assertNotIsInstance(self.x + self.pi, Constant)
+        xx = Expression({'x': 2})
+        self.assertNotIsInstance(xx, Symbol)
+        with self.assertRaises(TypeError):
+            Expression('x + y', 2)
+        self.assertEqual(Expression({'x': 2}), Expression({self.x: 2}))
+        with self.assertRaises(TypeError):
+            Expression({0: 2})
+        with self.assertRaises(TypeError):
+            Expression({'x': '2'})
+        self.assertEqual(Expression(constant=1), Expression(constant=self.one))
+        self.assertEqual(Expression(constant='1'), Expression(constant=self.one))
+        with self.assertRaises(ValueError):
+            Expression(constant='a')
+
+    def test_coefficient(self):
+        self.assertEqual(self.expr.coefficient('x'), 1)
+        self.assertEqual(self.expr.coefficient('y'), -2)
+        self.assertEqual(self.expr.coefficient(self.y), -2)
+        self.assertEqual(self.expr.coefficient('z'), 0)
+        with self.assertRaises(TypeError):
+            self.expr.coefficient(0)
+        with self.assertRaises(TypeError):
+            self.expr.coefficient(self.expr)
+
+    def test_getitem(self):
+        self.assertEqual(self.expr['x'], 1)
+        self.assertEqual(self.expr['y'], -2)
+        self.assertEqual(self.expr[self.y], -2)
+        self.assertEqual(self.expr['z'], 0)
+        with self.assertRaises(TypeError):
+            self.expr[0]
+        with self.assertRaises(TypeError):
+            self.expr[self.expr]
+
+    def test_coefficients(self):
+        self.assertCountEqual(self.expr.coefficients(), [('x', 1), ('y', -2)])
+
+    def test_constant(self):
+        self.assertEqual(self.x.constant, 0)
+        self.assertEqual(self.pi.constant, Fraction(22, 7))
+        self.assertEqual(self.expr.constant, 3)
+
+    def test_symbols(self):
+        self.assertCountEqual(self.x.symbols, ['x'])
+        self.assertCountEqual(self.pi.symbols, [])
+        self.assertCountEqual(self.expr.symbols, ['x', 'y'])
+
+    def test_dimension(self):
+        self.assertEqual(self.x.dimension, 1)
+        self.assertEqual(self.pi.dimension, 0)
+        self.assertEqual(self.expr.dimension, 2)
+
+    def test_isconstant(self):
+        self.assertFalse(self.x.isconstant())
+        self.assertTrue(self.pi.isconstant())
+        self.assertFalse(self.expr.isconstant())
+
+    def test_issymbol(self):
+        self.assertTrue(self.x.issymbol())
+        self.assertFalse(self.pi.issymbol())
+        self.assertFalse(self.expr.issymbol())
+
+    def test_values(self):
+        self.assertCountEqual(self.expr.values(), [1, -2, 3])
+
+    def test_bool(self):
+        self.assertTrue(self.x)
+        self.assertFalse(self.zero)
+        self.assertTrue(self.pi)
+        self.assertTrue(self.expr)
+
+    def test_pos(self):
+        self.assertEqual(+self.expr, self.expr)
+
+    def test_neg(self):
+        self.assertEqual(-self.expr, -self.x + 2*self.y - 3)
+
+    def test_add(self):
+        self.assertEqual(self.x + Fraction(22, 7), self.x + self.pi)
+        self.assertEqual(Fraction(22, 7) + self.x, self.x + self.pi)
+        self.assertEqual(self.x + self.x, 2 * self.x)
+        self.assertEqual(self.expr + 2*self.y, self.x + 3)
+
+    def test_sub(self):
+        self.assertEqual(self.x - self.x, 0)
+        self.assertEqual(self.expr - 3, self.x - 2*self.y)
+        self.assertEqual(0 - self.x, -self.x)
+
+    def test_mul(self):
+        self.assertEqual(self.pi * 7, 22)
+        self.assertEqual(self.expr * 0, 0)
+        self.assertEqual(0 * self.expr, 0)
+        self.assertEqual(self.expr * 2, 2*self.x - 4*self.y + 6)
+
+    def test_truediv(self):
+        with self.assertRaises(ZeroDivisionError):
+            self.expr / 0
+        self.assertEqual(self.expr / 2, self.x / 2 - self.y + Fraction(3, 2))
+
+    def test_eq(self):
+        self.assertEqual(self.expr, self.expr)
+        self.assertNotEqual(self.x, self.y)
+        self.assertEqual(self.zero, 0)
+
+    def test__toint(self):
+        self.assertEqual((self.x + self.y/2 + self.z/3)._toint(),
+                6*self.x + 3*self.y + 2*self.z)
+
+    def test_fromstring(self):
+        self.assertEqual(Expression.fromstring('x'), self.x)
+        self.assertEqual(Expression.fromstring('-x'), -self.x)
+        self.assertEqual(Expression.fromstring('22/7'), self.pi)
+        self.assertEqual(Expression.fromstring('x - 2y + 3'), self.expr)
+        self.assertEqual(Expression.fromstring('x - (3-1)y + 3'), self.expr)
+        self.assertEqual(Expression.fromstring('x - 2*y + 3'), self.expr)
+
+    def test_str(self):
+        self.assertEqual(str(Expression()), '0')
+        self.assertEqual(str(self.x), 'x')
+        self.assertEqual(str(-self.x), '-x')
+        self.assertEqual(str(self.pi), '22/7')
+        self.assertEqual(str(self.expr), 'x - 2*y + 3')
+
+    def test_repr(self):
+        self.assertEqual(repr(self.x), "Symbol('x')")
+        self.assertEqual(repr(self.one), 'Constant(1)')
+        self.assertEqual(repr(self.pi), 'Constant(22, 7)')
+        self.assertEqual(repr(self.x + self.one), "Expression('x + 1')")
+        self.assertEqual(repr(self.expr), "Expression('x - 2*y + 3')")
+
+    @_requires_sympy
+    def test_fromsympy(self):
+        sp_x, sp_y = sympy.symbols('x y')
+        self.assertEqual(Expression.fromsympy(sp_x), self.x)
+        self.assertEqual(Expression.fromsympy(sympy.Rational(22, 7)), self.pi)
+        self.assertEqual(Expression.fromsympy(sp_x - 2*sp_y + 3), self.expr)
+        with self.assertRaises(ValueError):
+            Expression.fromsympy(sp_x*sp_y)
+
+    @_requires_sympy
+    def test_tosympy(self):
+        sp_x, sp_y = sympy.symbols('x y')
+        self.assertEqual(self.x.tosympy(), sp_x)
+        self.assertEqual(self.pi.tosympy(), sympy.Rational(22, 7))
+        self.assertEqual(self.expr.tosympy(), sp_x - 2*sp_y + 3)
+
+
+class TestSymbol(unittest.TestCase):
+
+    def setUp(self):
+        self.x = Symbol('x')
+        self.y = Symbol('y')
+
+    def test_new(self):
+        self.assertEqual(Symbol(' x '), self.x)
+        self.assertEqual(Symbol(self.x), self.x)
+        with self.assertRaises(TypeError):
+            Symbol(1)
+
+    def test_name(self):
+        self.assertEqual(self.x.name, 'x')
+
+    def test_issymbol(self):
+        self.assertTrue(self.x.issymbol())
+
+    def test_fromstring(self):
+        self.assertEqual(Symbol.fromstring('x'), self.x)
+        with self.assertRaises(SyntaxError):
+            Symbol.fromstring('1')
+
+    def test_str(self):
+        self.assertEqual(str(self.x), 'x')
+
+    def test_repr(self):
+        self.assertEqual(repr(self.x), "Symbol('x')")
+
+    @_requires_sympy
+    def test_fromsympy(self):
+        sp_x = sympy.Symbol('x')
+        self.assertEqual(Symbol.fromsympy(sp_x), self.x)
+        with self.assertRaises(TypeError):
+            Symbol.fromsympy(sympy.Rational(22, 7))
+        with self.assertRaises(TypeError):
+            Symbol.fromsympy(2 * sp_x)
+        with self.assertRaises(TypeError):
+            Symbol.fromsympy(sp_x*sp_x)
+
+    def test_symbols(self):
+        self.assertListEqual(list(symbols('x y')), [self.x, self.y])
+        self.assertListEqual(list(symbols('x,y')), [self.x, self.y])
+        self.assertListEqual(list(symbols(['x', 'y'])), [self.x, self.y])
+
+
+class TestConstant(unittest.TestCase):
+
+    def setUp(self):
+        self.zero = Constant(0)
+        self.one = Constant(1)
+        self.pi = Constant(Fraction(22, 7))
+
+    def test_new(self):
+        self.assertEqual(Constant(), self.zero)
+        self.assertEqual(Constant(1), self.one)
+        self.assertEqual(Constant(self.pi), self.pi)
+        self.assertEqual(Constant('22/7'), self.pi)
+
+    def test_isconstant(self):
+        self.assertTrue(self.zero.isconstant())
+
+    def test_bool(self):
+        self.assertFalse(self.zero)
+        self.assertTrue(self.pi)
+
+    def test_fromstring(self):
+        self.assertEqual(Constant.fromstring('22/7'), self.pi)
+        with self.assertRaises(ValueError):
+            Constant.fromstring('a')
+        with self.assertRaises(TypeError):
+            Constant.fromstring(1)
+
+    def test_repr(self):
+        self.assertEqual(repr(self.zero), 'Constant(0)')
+        self.assertEqual(repr(self.one), 'Constant(1)')
+        self.assertEqual(repr(self.pi), 'Constant(22, 7)')
+
+    @_requires_sympy
+    def test_fromsympy(self):
+        self.assertEqual(Constant.fromsympy(sympy.Rational(22, 7)), self.pi)
+        with self.assertRaises(TypeError):
+            Constant.fromsympy(sympy.Symbol('x'))