+ _RE_COORDINATE = re.compile(r'\((?P<num>\-?\d+)\)(/(?P<den>\d+))?')
+
+ def vertices(self):
+ #returning list of verticies
+ from .polyhedra import Polyhedron
+ islbset = self._toislbasicset(self.equalities, self.inequalities, self.symbols)
+ vertices = libisl.isl_basic_set_compute_vertices(islbset);
+ vertices = islhelper.isl_vertices_vertices(vertices)
+ points = {}
+ num = 0
+ vertices_points = []
+ for vertex in vertices:
+ if islhelper.isl_version < '0.13':
+ expr = libisl.isl_vertex_get_expr(vertex)
+ constraints = islhelper.isl_basic_set_constraints(expr) #get bset constraints
+ for index, dim in enumerate(self.symbols):
+ for c in constraints: #for each constraint
+ constant = libisl.isl_constraint_get_constant_val(c) #get constant value
+ constant = islhelper.isl_val_to_int(constant)
+ coefficient = libisl.isl_constraint_get_coefficient_val(c,libisl.isl_dim_set, index)
+ coefficient = islhelper.isl_val_to_int(coefficient) #get coefficient
+ if coefficient != 0:
+ num = -Fraction(constant, coefficient)
+ points[dim]= float(num)
+ vertices_points.append(points.copy())
+ else:
+ points = []
+ string = islhelper.isl_multi_aff_to_str(expr)
+ matches = self._RE_COORDINATE.finditer(string)
+ point = {}
+ 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)
+ coordinate = Fraction(numerator, denominator)
+ point[symbol] = coordinate
+ points.append(point)
+ return vertices_points
+
+ def points(self):
+ 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:
+ point = {}
+ for index, symbol in enumerate(self.symbols):
+ coordinate = libisl.isl_point_get_coordinate_val(islpoint,
+ libisl.isl_dim_set, index)
+ coordinate = islhelper.isl_val_to_int(coordinate)
+ point[symbol] = coordinate
+ points.append(point)
+ return points
+
+ def subs(self, symbol, expression=None):
+ polyhedra = [polyhedron.subs(symbol, expression)
+ for polyhedron in self.polyhedra]
+ return Domain(*polyhedra)
+