PEP 8
[linpy.git] / linpy / domains.py
index 432e275..7f4fa65 100644 (file)
@@ -23,14 +23,16 @@ import math
 from fractions import Fraction
 
 from . import islhelper
-from .islhelper import mainctx, libisl
-from .linexprs import LinExpr, Symbol
 from .geometry import GeometricObject, Point, Vector
+from .islhelper import libisl
+from .linexprs import LinExpr, Symbol
 
 
 __all__ = [
+    'And',
     'Domain',
-    'And', 'Or', 'Not',
+    'Not',
+    'Or',
 ]
 
 
@@ -84,7 +86,7 @@ class Domain(GeometricObject):
                 return argument.aspolyhedron()
             else:
                 raise TypeError('argument must be a string '
-                    'or a GeometricObject instance')
+                                'or a GeometricObject instance')
         else:
             for polyhedron in polyhedra:
                 if not isinstance(polyhedron, Polyhedron):
@@ -235,7 +237,7 @@ class Domain(GeometricObject):
         Return an equivalent domain, whose polyhedra are disjoint.
         """
         islset = self._toislset(self.polyhedra, self.symbols)
-        islset = libisl.isl_set_make_disjoint(mainctx, islset)
+        islset = libisl.isl_set_make_disjoint(islset)
         return self._fromislset(islset, self.symbols)
 
     def coalesce(self):
@@ -289,11 +291,12 @@ class Domain(GeometricObject):
             if symbol in symbols:
                 n += 1
             elif n > 0:
-                islset = libisl.isl_set_project_out(islset,
-                    libisl.isl_dim_set, index + 1, n)
+                islset = libisl.isl_set_project_out(
+                    islset, libisl.isl_dim_set, index + 1, n)
                 n = 0
         if n > 0:
-            islset = libisl.isl_set_project_out(islset, libisl.isl_dim_set, 0, n)
+            islset = libisl.isl_set_project_out(
+                islset, libisl.isl_dim_set, 0, n)
         symbols = [symbol for symbol in self.symbols if symbol not in symbols]
         return Domain._fromislset(islset, symbols)
 
@@ -309,8 +312,8 @@ class Domain(GeometricObject):
             raise ValueError('domain must be non-empty')
         point = {}
         for index, symbol in enumerate(self.symbols):
-            coordinate = libisl.isl_point_get_coordinate_val(islpoint,
-                libisl.isl_dim_set, index)
+            coordinate = libisl.isl_point_get_coordinate_val(
+                islpoint, libisl.isl_dim_set, index)
             coordinate = islhelper.isl_val_to_int(coordinate)
             point[symbol] = coordinate
         libisl.isl_point_free(islpoint)
@@ -402,36 +405,38 @@ class Domain(GeometricObject):
         Return the vertices of the domain, as a list of rational instances of
         Point.
         """
-        from .polyhedra import Polyhedron
         if not self.isbounded():
             raise ValueError('domain must be bounded')
         islbset = self._toislbasicset(self.equalities, self.inequalities,
-            self.symbols)
-        vertices = libisl.isl_basic_set_compute_vertices(islbset);
+                                      self.symbols)
+        vertices = libisl.isl_basic_set_compute_vertices(islbset)
         vertices = islhelper.isl_vertices_vertices(vertices)
         points = []
         for vertex in vertices:
-            expr = libisl.isl_vertex_get_expr(vertex)
+            expression = libisl.isl_vertex_get_expr(vertex)
             coordinates = []
             if self._RE_COORDINATE is None:
-                constraints = islhelper.isl_basic_set_constraints(expr)
+                constraints = islhelper.isl_basic_set_constraints(expression)
                 for constraint in constraints:
-                    constant = libisl.isl_constraint_get_constant_val(constraint)
+                    constant = libisl.isl_constraint_get_constant_val(
+                        constraint)
                     constant = islhelper.isl_val_to_int(constant)
                     for index, symbol in enumerate(self.symbols):
-                        coefficient = libisl.isl_constraint_get_coefficient_val(constraint,
-                            libisl.isl_dim_set, index)
+                        coefficient = \
+                            libisl.isl_constraint_get_coefficient_val(
+                                constraint, libisl.isl_dim_set, index)
                         coefficient = islhelper.isl_val_to_int(coefficient)
                         if coefficient != 0:
                             coordinate = -Fraction(constant, coefficient)
                             coordinates.append((symbol, coordinate))
             else:
-                string = islhelper.isl_multi_aff_to_str(expr)
+                string = islhelper.isl_multi_aff_to_str(expression)
                 matches = self._RE_COORDINATE.finditer(string)
                 for symbol, match in zip(self.symbols, matches):
                     numerator = int(match.group('num'))
                     denominator = match.group('den')
-                    denominator = 1 if denominator is None else int(denominator)
+                    denominator = \
+                        1 if denominator is None else int(denominator)
                     coordinate = Fraction(numerator, denominator)
                     coordinates.append((symbol, coordinate))
             points.append(Point(coordinates))
@@ -440,20 +445,19 @@ class Domain(GeometricObject):
     def points(self):
         """
         Return the integer points of a bounded domain, as a list of integer
-        instances of Point. If the domain is not bounded, a ValueError exception
-        is raised.
+        instances of Point. If the domain is not bounded, a ValueError
+        exception is raised.
         """
         if not self.isbounded():
             raise ValueError('domain must be bounded')
-        from .polyhedra import Universe, Eq
         islset = self._toislset(self.polyhedra, self.symbols)
         islpoints = islhelper.isl_set_points(islset)
         points = []
         for islpoint in islpoints:
             coordinates = {}
             for index, symbol in enumerate(self.symbols):
-                coordinate = libisl.isl_point_get_coordinate_val(islpoint,
-                    libisl.isl_dim_set, index)
+                coordinate = libisl.isl_point_get_coordinate_val(
+                    islpoint, libisl.isl_dim_set, index)
                 coordinate = islhelper.isl_val_to_int(coordinate)
                 coordinates[symbol] = coordinate
             points.append(Point(coordinates))
@@ -610,7 +614,7 @@ class Domain(GeometricObject):
         similar to LinExpr.subs().
         """
         polyhedra = [polyhedron.subs(symbol, expression)
-            for polyhedron in self.polyhedra]
+                     for polyhedron in self.polyhedra]
         return Domain(*polyhedra)
 
     @classmethod
@@ -638,12 +642,12 @@ class Domain(GeometricObject):
     @classmethod
     def _toislset(cls, polyhedra, symbols):
         polyhedron = polyhedra[0]
-        islbset = polyhedron._toislbasicset(polyhedron.equalities,
-            polyhedron.inequalities, symbols)
+        islbset = polyhedron._toislbasicset(
+            polyhedron.equalities, polyhedron.inequalities, symbols)
         islset1 = libisl.isl_set_from_basic_set(islbset)
         for polyhedron in polyhedra[1:]:
-            islbset = polyhedron._toislbasicset(polyhedron.equalities,
-                polyhedron.inequalities, symbols)
+            islbset = polyhedron._toislbasicset(
+                polyhedron.equalities, polyhedron.inequalities, symbols)
             islset2 = libisl.isl_set_from_basic_set(islbset)
             islset1 = libisl.isl_set_union(islset1, islset2)
         return islset1
@@ -730,7 +734,7 @@ class Domain(GeometricObject):
         return 'Or({})'.format(', '.join(strings))
 
     @classmethod
-    def fromsympy(cls, expr):
+    def fromsympy(cls, expression):
         """
         Create a domain from a SymPy expression.
         """
@@ -742,19 +746,19 @@ class Domain(GeometricObject):
             sympy.Eq: Eq, sympy.Ne: Ne,
             sympy.Ge: Ge, sympy.Gt: Gt,
         }
-        if expr.func in funcmap:
-            args = [Domain.fromsympy(arg) for arg in expr.args]
-            return funcmap[expr.func](*args)
-        elif isinstance(expr, sympy.Expr):
-            return LinExpr.fromsympy(expr)
-        raise ValueError('non-domain expression: {!r}'.format(expr))
+        if expression.func in funcmap:
+            args = [Domain.fromsympy(arg) for arg in expression.args]
+            return funcmap[expression.func](*args)
+        elif isinstance(expression, sympy.Expr):
+            return LinExpr.fromsympy(expression)
+        raise ValueError('non-domain expression: {!r}'.format(expression))
 
     def tosympy(self):
         """
         Convert the domain to a SymPy expression.
         """
         import sympy
-        polyhedra = [polyhedron.tosympy() for polyhedron in polyhedra]
+        polyhedra = [polyhedron.tosympy() for polyhedron in self.polyhedra]
         return sympy.Or(*polyhedra)
 
 
@@ -768,6 +772,7 @@ def And(*domains):
     else:
         return domains[0].intersection(*domains[1:])
 
+
 def Or(*domains):
     """
     Create the union domain of the domains given in arguments.
@@ -778,6 +783,7 @@ def Or(*domains):
     else:
         return domains[0].union(*domains[1:])
 
+
 def Not(domain):
     """
     Create the complementary domain of the domain given in argument.