X-Git-Url: https://scm.cri.ensmp.fr/git/linpy.git/blobdiff_plain/ba15f3f33f837b1291f74bc94081e99b860d3228..2b13a146860ac116ce0388d8f7551044c09c55f7:/linpy/domains.py?ds=sidebyside

diff --git a/linpy/domains.py b/linpy/domains.py
index 4cd46a4..432e275 100644
--- a/linpy/domains.py
+++ b/linpy/domains.py
@@ -24,7 +24,7 @@ from fractions import Fraction
 
 from . import islhelper
 from .islhelper import mainctx, libisl
-from .linexprs import LinExpr, Symbol, Rational
+from .linexprs import LinExpr, Symbol
 from .geometry import GeometricObject, Point, Vector
 
 
@@ -38,7 +38,7 @@ __all__ = [
 class Domain(GeometricObject):
     """
     A domain is a union of polyhedra. Unlike polyhedra, domains allow exact
-    computation of union and complementary operations.
+    computation of union, subtraction and complementary operations.
 
     A domain with a unique polyhedron is automatically subclassed as a
     Polyhedron instance.
@@ -54,22 +54,23 @@ class Domain(GeometricObject):
         """
         Return a domain from a sequence of polyhedra.
 
-        >>> square = Polyhedron('0 <= x <= 2, 0 <= y <= 2')
-        >>> square2 = Polyhedron('2 <= x <= 4, 2 <= y <= 4')
-        >>> dom = Domain([square, square2])
+        >>> square1 = Polyhedron('0 <= x <= 2, 0 <= y <= 2')
+        >>> square2 = Polyhedron('1 <= x <= 3, 1 <= y <= 3')
+        >>> dom = Domain(square1, square2)
+        >>> dom
+        Or(And(x <= 2, 0 <= x, y <= 2, 0 <= y),
+           And(x <= 3, 1 <= x, y <= 3, 1 <= y))
 
         It is also possible to build domains from polyhedra using arithmetic
-        operators Domain.__and__(), Domain.__or__() or functions And() and Or(),
-        using one of the following instructions:
+        operators Domain.__or__(), Domain.__invert__() or functions Or() and
+        Not(), using one of the following instructions:
 
-        >>> square = Polyhedron('0 <= x <= 2, 0 <= y <= 2')
-        >>> square2 = Polyhedron('2 <= x <= 4, 2 <= y <= 4')
-        >>> dom = square | square2
-        >>> dom = Or(square, square2)
+        >>> dom = square1 | square2
+        >>> dom = Or(square1, square2)
 
         Alternatively, a domain can be built from a string:
 
-        >>> dom = Domain('0 <= x <= 2, 0 <= y <= 2; 2 <= x <= 4, 2 <= y <= 4')
+        >>> dom = Domain('0 <= x <= 2, 0 <= y <= 2; 1 <= x <= 3, 1 <= y <= 3')
 
         Finally, a domain can be built from a GeometricObject instance, calling
         the GeometricObject.asdomain() method.
@@ -161,18 +162,22 @@ class Domain(GeometricObject):
         """
         Return True if two domains are equal.
         """
-        symbols = self._xsymbols([self, other])
-        islset1 = self._toislset(self.polyhedra, symbols)
-        islset2 = other._toislset(other.polyhedra, symbols)
-        equal = bool(libisl.isl_set_is_equal(islset1, islset2))
-        libisl.isl_set_free(islset1)
-        libisl.isl_set_free(islset2)
-        return equal
+        if isinstance(other, Domain):
+            symbols = self._xsymbols([self, other])
+            islset1 = self._toislset(self.polyhedra, symbols)
+            islset2 = other._toislset(other.polyhedra, symbols)
+            equal = bool(libisl.isl_set_is_equal(islset1, islset2))
+            libisl.isl_set_free(islset1)
+            libisl.isl_set_free(islset2)
+            return equal
+        return NotImplemented
 
     def isdisjoint(self, other):
         """
         Return True if two domains have a null intersection.
         """
+        if not isinstance(other, Domain):
+            raise TypeError('other must be a Domain instance')
         symbols = self._xsymbols([self, other])
         islset1 = self._toislset(self.polyhedra, symbols)
         islset2 = self._toislset(other.polyhedra, symbols)
@@ -185,29 +190,33 @@ class Domain(GeometricObject):
         """
         Report whether another domain contains the domain.
         """
-        symbols = self._xsymbols([self, other])
-        islset1 = self._toislset(self.polyhedra, symbols)
-        islset2 = self._toislset(other.polyhedra, symbols)
-        equal = bool(libisl.isl_set_is_subset(islset1, islset2))
-        libisl.isl_set_free(islset1)
-        libisl.isl_set_free(islset2)
-        return equal
+        return self < other
 
     def __le__(self, other):
-        return self.issubset(other)
+        if isinstance(other, Domain):
+            symbols = self._xsymbols([self, other])
+            islset1 = self._toislset(self.polyhedra, symbols)
+            islset2 = self._toislset(other.polyhedra, symbols)
+            equal = bool(libisl.isl_set_is_subset(islset1, islset2))
+            libisl.isl_set_free(islset1)
+            libisl.isl_set_free(islset2)
+            return equal
+        return NotImplemented
     __le__.__doc__ = issubset.__doc__
 
     def __lt__(self, other):
         """
         Report whether another domain is contained within the domain.
         """
-        symbols = self._xsymbols([self, other])
-        islset1 = self._toislset(self.polyhedra, symbols)
-        islset2 = self._toislset(other.polyhedra, symbols)
-        equal = bool(libisl.isl_set_is_strict_subset(islset1, islset2))
-        libisl.isl_set_free(islset1)
-        libisl.isl_set_free(islset2)
-        return equal
+        if isinstance(other, Domain):
+            symbols = self._xsymbols([self, other])
+            islset1 = self._toislset(self.polyhedra, symbols)
+            islset2 = self._toislset(other.polyhedra, symbols)
+            equal = bool(libisl.isl_set_is_strict_subset(islset1, islset2))
+            libisl.isl_set_free(islset1)
+            libisl.isl_set_free(islset2)
+            return equal
+        return NotImplemented
 
     def complement(self):
         """
@@ -270,6 +279,10 @@ class Domain(GeometricObject):
         Project out the sequence of symbols given in arguments, and return the
         resulting domain.
         """
+        symbols = list(symbols)
+        for symbol in symbols:
+            if not isinstance(symbol, Symbol):
+                raise TypeError('symbols must be Symbol instances')
         islset = self._toislset(self.polyhedra, self.symbols)
         n = 0
         for index, symbol in reversed(list(enumerate(self.symbols))):
@@ -308,17 +321,19 @@ class Domain(GeometricObject):
         Return the intersection of two or more domains as a new domain. As an
         alternative, function And() can be used.
         """
-        if len(others) == 0:
-            return self
-        symbols = self._xsymbols((self,) + others)
-        islset1 = self._toislset(self.polyhedra, symbols)
+        result = self
         for other in others:
-            islset2 = other._toislset(other.polyhedra, symbols)
-            islset1 = libisl.isl_set_intersect(islset1, islset2)
-        return self._fromislset(islset1, symbols)
+            result &= other
+        return result
 
     def __and__(self, other):
-        return self.intersection(other)
+        if isinstance(other, Domain):
+            symbols = self._xsymbols([self, other])
+            islset1 = self._toislset(self.polyhedra, symbols)
+            islset2 = other._toislset(other.polyhedra, symbols)
+            islset = libisl.isl_set_intersect(islset1, islset2)
+            return self._fromislset(islset, symbols)
+        return NotImplemented
     __and__.__doc__ = intersection.__doc__
 
     def union(self, *others):
@@ -326,35 +341,39 @@ class Domain(GeometricObject):
         Return the union of two or more domains as a new domain. As an
         alternative, function Or() can be used.
         """
-        if len(others) == 0:
-            return self
-        symbols = self._xsymbols((self,) + others)
-        islset1 = self._toislset(self.polyhedra, symbols)
+        result = self
         for other in others:
-            islset2 = other._toislset(other.polyhedra, symbols)
-            islset1 = libisl.isl_set_union(islset1, islset2)
-        return self._fromislset(islset1, symbols)
+            result |= other
+        return result
 
     def __or__(self, other):
-        return self.union(other)
+        if isinstance(other, Domain):
+            symbols = self._xsymbols([self, other])
+            islset1 = self._toislset(self.polyhedra, symbols)
+            islset2 = other._toislset(other.polyhedra, symbols)
+            islset = libisl.isl_set_union(islset1, islset2)
+            return self._fromislset(islset, symbols)
+        return NotImplemented
     __or__.__doc__ = union.__doc__
 
     def __add__(self, other):
-        return self.union(other)
+        return self | other
     __add__.__doc__ = union.__doc__
 
     def difference(self, other):
         """
         Return the difference of two domains as a new domain.
         """
-        symbols = self._xsymbols([self, other])
-        islset1 = self._toislset(self.polyhedra, symbols)
-        islset2 = other._toislset(other.polyhedra, symbols)
-        islset = libisl.isl_set_subtract(islset1, islset2)
-        return self._fromislset(islset, symbols)
+        return self - other
 
     def __sub__(self, other):
-        return self.difference(other)
+        if isinstance(other, Domain):
+            symbols = self._xsymbols([self, other])
+            islset1 = self._toislset(self.polyhedra, symbols)
+            islset2 = other._toislset(other.polyhedra, symbols)
+            islset = libisl.isl_set_subtract(islset1, islset2)
+            return self._fromislset(islset, symbols)
+        return NotImplemented
     __sub__.__doc__ = difference.__doc__
 
     def lexmin(self):
@@ -373,7 +392,10 @@ class Domain(GeometricObject):
         islset = libisl.isl_set_lexmax(islset)
         return self._fromislset(islset, self.symbols)
 
-    _RE_COORDINATE = re.compile(r'\((?P<num>\-?\d+)\)(/(?P<den>\d+))?')
+    if islhelper.isl_version >= '0.13':
+        _RE_COORDINATE = re.compile(r'\((?P<num>\-?\d+)\)(/(?P<den>\d+))?')
+    else:
+        _RE_COORDINATE = None
 
     def vertices(self):
         """
@@ -391,7 +413,7 @@ class Domain(GeometricObject):
         for vertex in vertices:
             expr = libisl.isl_vertex_get_expr(vertex)
             coordinates = []
-            if islhelper.isl_version < '0.13':
+            if self._RE_COORDINATE is None:
                 constraints = islhelper.isl_basic_set_constraints(expr)
                 for constraint in constraints:
                     constant = libisl.isl_constraint_get_constant_val(constraint)
@@ -578,7 +600,7 @@ class Domain(GeometricObject):
         elif self.dimension == 3:
             return self._plot_3d(plot=plot, **kwargs)
         else:
-            raise ValueError('polyhedron must be 2 or 3-dimensional')
+            raise ValueError('domain must be 2 or 3-dimensional')
 
     def subs(self, symbol, expression=None):
         """
@@ -682,17 +704,17 @@ class Domain(GeometricObject):
         Create a domain from a string. Raise SyntaxError if the string is not
         properly formatted.
         """
-        # remove curly brackets
+        # Remove curly brackets.
         string = cls._RE_BRACES.sub(r'', string)
-        # replace '=' by '=='
+        # Replace '=' by '=='.
         string = cls._RE_EQ.sub(r'\1==\2', string)
-        # replace 'and', 'or', 'not'
+        # Replace 'and', 'or', 'not'.
         string = cls._RE_AND.sub(r' & ', string)
         string = cls._RE_OR.sub(r' | ', string)
         string = cls._RE_NOT.sub(r' ~', string)
-        # add implicit multiplication operators, e.g. '5x' -> '5*x'
+        # Add implicit multiplication operators, e.g. '5x' -> '5*x'.
         string = cls._RE_NUM_VAR.sub(r'\1*\2', string)
-        # add parentheses to force precedence
+        # Add parentheses to force precedence.
         tokens = cls._RE_OPERATORS.split(string)
         for i, token in enumerate(tokens):
             if i % 2 == 0:
@@ -707,16 +729,10 @@ class Domain(GeometricObject):
         strings = [repr(polyhedron) for polyhedron in self.polyhedra]
         return 'Or({})'.format(', '.join(strings))
 
-    def _repr_latex_(self):
-        strings = []
-        for polyhedron in self.polyhedra:
-            strings.append('({})'.format(polyhedron._repr_latex_().strip('$')))
-        return '${}$'.format(' \\vee '.join(strings))
-
     @classmethod
     def fromsympy(cls, expr):
         """
-        Create a domain from a sympy expression.
+        Create a domain from a SymPy expression.
         """
         import sympy
         from .polyhedra import Lt, Le, Eq, Ne, Ge, Gt
@@ -735,7 +751,7 @@ class Domain(GeometricObject):
 
     def tosympy(self):
         """
-        Convert the domain to a sympy expression.
+        Convert the domain to a SymPy expression.
         """
         import sympy
         polyhedra = [polyhedron.tosympy() for polyhedron in polyhedra]
@@ -751,7 +767,6 @@ def And(*domains):
         return Universe
     else:
         return domains[0].intersection(*domains[1:])
-And.__doc__ = Domain.intersection.__doc__
 
 def Or(*domains):
     """
@@ -762,11 +777,9 @@ def Or(*domains):
         return Empty
     else:
         return domains[0].union(*domains[1:])
-Or.__doc__ = Domain.union.__doc__
 
 def Not(domain):
     """
     Create the complementary domain of the domain given in argument.
     """
     return ~domain
-Not.__doc__ = Domain.complement.__doc__