X-Git-Url: https://scm.cri.ensmp.fr/git/linpy.git/blobdiff_plain/62fbaa7984d8035cccc97555f1de3188e280e475..950e4adf4d155a2880fbfcd61021f775dfddaeac:/linpy/domains.py

diff --git a/linpy/domains.py b/linpy/domains.py
index 9fdc7d5..0da0a49 100644
--- a/linpy/domains.py
+++ b/linpy/domains.py
@@ -391,7 +391,10 @@ 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):
         """
@@ -409,7 +412,7 @@ 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)
@@ -596,7 +599,7 @@ 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):
         """
@@ -734,7 +737,7 @@ class Domain(GeometricObject):
     @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
@@ -753,7 +756,7 @@ 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]