Add methods Domain.subs(), Polyhedron.subs()

[linpy.git] / pypol / domains.py

diff --git a/pypol/domains.py b/pypol/domains.py
index 224ac5f..2fbd544 100644 (file)
--- a/pypol/domains.py
+++ b/pypol/domains.py
@@ -2,8 +2,9 @@ import ast
 import functools
 import re
 
 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
 
 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)
 
         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
         # several types of hull are available
         # polyhedral seems to be the more appropriate, to be checked
         from .polyhedra import Polyhedron


@@ -152,26 +153,35 @@ class Domain:
         islbset = libisl.isl_set_polyhedral_hull(islset)
         return Polyhedron._fromislbasicset(islbset, self.symbols)
 
         islbset = libisl.isl_set_polyhedral_hull(islset)
         return Polyhedron._fromislbasicset(islbset, self.symbols)
 

-    def project_out(self, symbols):
+    def project(self, dims):

         # use to remove certain variables
         islset = self._toislset(self.polyhedra, self.symbols)
         n = 0
         for index, symbol in reversed(list(enumerate(self.symbols))):
         # use to remove certain variables
         islset = self._toislset(self.polyhedra, self.symbols)
         n = 0
         for index, symbol in reversed(list(enumerate(self.symbols))):

-            if symbol in symbols:
+            if symbol in dims:

                 n += 1
             elif n > 0:
                 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)
                 n += 1
             elif n > 0:
                 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)

-        symbols = [symbol for symbol in self.symbols if symbol not in symbols]
-        return Domain._fromislset(islset, symbols)
+        dims = [symbol for symbol in self.symbols if symbol not in dims]
+        return Domain._fromislset(islset, dims)

 
     def sample(self):
 
     def sample(self):

-        from .polyhedra import Polyhedron

         islset = self._toislset(self.polyhedra, self.symbols)
         islset = self._toislset(self.polyhedra, self.symbols)

-        islbset = libisl.isl_set_sample(islset)
-        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:
 
     def intersection(self, *others):
         if len(others) == 0:


@@ -222,6 +232,80 @@ class Domain:
         islset = libisl.isl_set_lexmax(islset)
         return self._fromislset(islset, self.symbols)
 
         islset = libisl.isl_set_lexmax(islset)
         return self._fromislset(islset, self.symbols)
 

+    def num_parameters(self):
+        #could be useful with large, complicated polyhedrons
+        islbset = self._toislbasicset(self.equalities, self.inequalities, self.symbols)
+        num = libisl.isl_basic_set_dim(islbset, libisl.isl_dim_set)
+        return num
+
+    def involves_dims(self, dims):
+        #could be useful with large, complicated polyhedrons
+        islset = self._toislset(self.polyhedra, self.symbols)
+        dims = sorted(dims)
+        symbols = sorted(list(self.symbols))
+        n = 0
+        if len(dims)>0:
+            for dim in dims:
+                if dim in symbols:
+                    first = symbols.index(dims[0])
+                    n +=1
+                else:
+                    first = 0
+        else:
+            return False
+        value = bool(libisl.isl_set_involves_dims(islset, libisl.isl_dim_set, first, n))
+        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)
+                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 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)
+

     @classmethod
     def _fromislset(cls, islset, symbols):
         from .polyhedra import Polyhedron
     @classmethod
     def _fromislset(cls, islset, symbols):
         from .polyhedra import Polyhedron


@@ -244,6 +328,7 @@ class Domain:
             self._dimension = len(self._symbols)
             return self
 
             self._dimension = len(self._symbols)
             return self
 

+    @classmethod

     def _toislset(cls, polyhedra, symbols):
         polyhedron = polyhedra[0]
         islbset = polyhedron._toislbasicset(polyhedron.equalities,
     def _toislset(cls, polyhedra, symbols):
         polyhedron = polyhedra[0]
         islbset = polyhedron._toislbasicset(polyhedron.equalities,