From: Vivien Maisonneuve Date: Thu, 3 Jul 2014 08:19:39 +0000 (+0200) Subject: Support for dummy symbols X-Git-Tag: 1.0~157 X-Git-Url: https://scm.cri.mines-paristech.fr/git/linpy.git/commitdiff_plain/161d0ced692386a866e55aea673d991e2e95f753?ds=inline;hp=9f4798446bbb3ac43f7b8291ddae095af3818299 Support for dummy symbols --- diff --git a/examples/nsad2010.py b/examples/nsad2010.py index e2cacc7..1bf97d8 100755 --- a/examples/nsad2010.py +++ b/examples/nsad2010.py @@ -2,17 +2,13 @@ from pypol import * -def affine_derivative_closure(T, x0s): +def affine_derivative_closure(T, x0s, xs): - xs = [Symbol("{}'".format(x0.name)) for x0 in x0s] - dxs = [Symbol('d{}'.format(x0.name)) for x0 in x0s] - k = Symbol('k') + dxs = [x0.asdummy() for x0 in x0s] + k = Dummy('k') for x in T.symbols: assert x in x0s + xs - for dx in dxs: - assert dx.name not in T.symbols - assert k.name not in T.symbols T0 = T @@ -48,5 +44,5 @@ i0, j0, i, j = symbols(['i', 'j', "i'", "j'"]) T = Eq(i, i0 + 2) & Eq(j, j0 + 1) print('T =', T) -Tstar = affine_derivative_closure(T, [i0, j0]) +Tstar = affine_derivative_closure(T, [i0, j0], [i, j]) print('T* =', Tstar) diff --git a/pypol/__init__.py b/pypol/__init__.py index 89f80fc..c81cb25 100644 --- a/pypol/__init__.py +++ b/pypol/__init__.py @@ -2,13 +2,13 @@ A polyhedral library based on ISL. """ -from .linexprs import Expression, Symbol, symbols, Rational +from .linexprs import Expression, Symbol, symbols, Dummy, Rational from .polyhedra import Polyhedron, Eq, Ne, Le, Lt, Ge, Gt, Ne, Empty, Universe from .domains import Domain, And, Or, Not __all__ = [ - 'Expression', 'Symbol', 'symbols', 'Rational', + 'Expression', 'Symbol', 'symbols', 'Dummy', 'Rational', 'Polyhedron', 'Eq', 'Ne', 'Le', 'Lt', 'Ge', 'Gt', 'Empty', 'Universe', 'Domain', 'And', 'Or', 'Not', ] diff --git a/pypol/linexprs.py b/pypol/linexprs.py index 73c6b0e..f3cff23 100644 --- a/pypol/linexprs.py +++ b/pypol/linexprs.py @@ -9,7 +9,7 @@ from fractions import Fraction, gcd __all__ = [ 'Expression', - 'Symbol', 'symbols', + 'Symbol', 'symbols', 'Dummy', 'Rational', ] @@ -355,7 +355,7 @@ class Symbol(Expression): return self._name def __hash__(self): - return hash(self._name) + return hash(self.sortkey()) def coefficient(self, symbol): if not isinstance(symbol, Symbol): @@ -390,7 +390,11 @@ class Symbol(Expression): yield 1 def __eq__(self, other): - return isinstance(other, Symbol) and self.name == other.name + return not isinstance(other, Dummy) and isinstance(other, Symbol) \ + and self.name == other.name + + def asdummy(self): + return Dummy(self.name) @classmethod def _fromast(cls, node): @@ -417,6 +421,34 @@ def symbols(names): return tuple(Symbol(name) for name in names) +class Dummy(Symbol): + + __slots__ = ( + '_name', + '_index', + ) + + _count = 0 + + def __new__(cls, name=None): + if name is None: + name = 'Dummy_{}'.format(Dummy._count) + self = object().__new__(cls) + self._name = name.strip() + self._index = Dummy._count + Dummy._count += 1 + return self + + def __hash__(self): + return hash(self.sortkey()) + + def sortkey(self): + return self._name, self._index + + def __eq__(self, other): + return isinstance(other, Dummy) and self._index == other._index + + class Rational(Expression): __slots__ = ( diff --git a/pypol/tests/test_linexprs.py b/pypol/tests/test_linexprs.py index adfec7d..508c57b 100644 --- a/pypol/tests/test_linexprs.py +++ b/pypol/tests/test_linexprs.py @@ -231,6 +231,23 @@ class TestSymbol(unittest.TestCase): self.assertListEqual(list(symbols(['x', 'y'])), [self.x, self.y]) +class TestDummy(unittest.TestCase): + + def setUp(self): + self.x = Dummy('x') + + def test_new(self): + self.assertEqual(self.x.name, 'x') + self.assertTrue(Dummy().name.startswith('Dummy')) + + def test_eq(self): + self.assertEqual(self.x, self.x) + self.assertNotEqual(self.x, Symbol('x')) + self.assertNotEqual(Symbol('x'), self.x) + self.assertNotEqual(self.x, Dummy('x')) + self.assertNotEqual(Dummy(), Dummy()) + + class TestRational(unittest.TestCase): def setUp(self):