Hacky way to get vertices with ISL 0.13

[linpy.git] / pypol / domains.py

diff --git a/pypol/domains.py b/pypol/domains.py
index dd39220..fdb0ab0 100644 (file)
--- a/pypol/domains.py
+++ b/pypol/domains.py
@@ -2,8 +2,9 @@ import ast
 import functools
 import re
 
-from . import islhelper
+from fractions import Fraction
 
+from . import islhelper
 from .islhelper import mainctx, libisl, isl_set_basic_sets
 from .linexprs import Expression, Symbol
 
@@ -144,7 +145,7 @@ class Domain:
         islset = libisl.isl_set_remove_redundancies(islset)
         return self._fromislset(islset, self.symbols)
 
-    def polyhedral_hull(self):
+    def aspolyhedron(self):
         # several types of hull are available
         # polyhedral seems to be the more appropriate, to be checked
         from .polyhedra import Polyhedron
@@ -168,12 +169,19 @@ class Domain:
         return Domain._fromislset(islset, dims)
 
     def sample(self):
-        from .polyhedra import Polyhedron
         islset = self._toislset(self.polyhedra, self.symbols)
-        islbset = libisl.isl_set_sample(islset)
-        # next instruction should NOT be required
-        islbset = libisl.isl_basic_set_finalize(islbset)
-        return Polyhedron._fromislbasicset(islbset, self.symbols)
+        islpoint = libisl.isl_set_sample_point(islset)
+        if bool(libisl.isl_point_is_void(islpoint)):
+            libisl.isl_point_free(islpoint)
+            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 = islhelper.isl_val_to_int(coordinate)
+            point[symbol] = coordinate
+        libisl.isl_point_free(islpoint)
+        return point
 
     def intersection(self, *others):
         if len(others) == 0:
@@ -249,21 +257,36 @@ class Domain:
         libisl.isl_set_free(islset)
         return value
 
+    _RE_COORDINATE = re.compile(r'\((?P<num>\-?\d+)\)(/(?P<den>\d+))?')
+
     def vertices(self):
         islbset = self._toislbasicset(self.equalities, self.inequalities, 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);
             if islhelper.isl_version < '0.13':
                 string = islhelper.isl_set_to_str(expr)
+                print(string)
+                # to be continued...
             else:
+                # horrible hack, find a cleaner solution
                 string = islhelper.isl_multi_aff_to_str(expr)
-            print(string)
+                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 points
 
     def points(self):
         if not self.isbounded():
-            raise ValueError('domain must be unbounded')
+            raise ValueError('domain must be bounded')
         from .polyhedra import Universe, Eq
         islset = self._toislset(self.polyhedra, self.symbols)
         islpoints = islhelper.isl_set_points(islset)