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

[linpy.git] / pypol / domains.py

diff --git a/pypol/domains.py b/pypol/domains.py
index 4a1f9aa..2fbd544 100644 (file)
--- a/pypol/domains.py
+++ b/pypol/domains.py
@@ -2,10 +2,11 @@ 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 .islhelper import mainctx, libisl, isl_set_basic_sets

-from .linexprs import Expression
+from .linexprs import Expression, Symbol

 
 
 __all__ = [
 
 
 __all__ = [


@@ -50,7 +51,7 @@ class Domain:
         symbols = set()
         for item in iterator:
             symbols.update(item.symbols)
         symbols = set()
         for item in iterator:
             symbols.update(item.symbols)

-        return tuple(sorted(symbols))
+        return tuple(sorted(symbols, key=Symbol.sortkey))

 
     @property
     def polyhedra(self):
 
     @property
     def polyhedra(self):


@@ -139,12 +140,12 @@ class Domain:
 
     def simplify(self):
         #does not change anything in any of the examples
 
     def simplify(self):
         #does not change anything in any of the examples

-        #isl seems to do this naturally 
+        #isl seems to do this naturally

         islset = self._toislset(self.polyhedra, self.symbols)
         islset = libisl.isl_set_remove_redundancies(islset)
         return self._fromislset(islset, self.symbols)
 
         islset = self._toislset(self.polyhedra, 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


@@ -152,23 +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 drop_dims(self, dims):
-        # use to remove certain variables use isl_set_drop_constraints_involving_dims instead?
-        from .polyhedra import Polyhedron       
-        dims = list(dims)
-        symbols = list(self.symbols)
+    def project(self, dims):
+        # use to remove certain variables

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

-        for dim in dims:
-            if dim in symbols:
-                num = symbols.index(dim)
-                islbset = libisl.isl_set_drop_constraints_involving_dims(islset, libisl.isl_dim_set, num, 1)
-        return Polyhedron._fromislset(islbset, self.symbols)
-    
+        n = 0
+        for index, symbol in reversed(list(enumerate(self.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)
+        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:


@@ -219,6 +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


@@ -241,6 +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,


@@ -332,10 +420,26 @@ class Domain:
 
     @classmethod
     def fromsympy(cls, expr):
 
     @classmethod
     def fromsympy(cls, expr):

-        raise NotImplementedError
+        import sympy
+        from .polyhedra import Lt, Le, Eq, Ne, Ge, Gt
+        funcmap = {
+            sympy.And: And, sympy.Or: Or, sympy.Not: Not,
+            sympy.Lt: Lt, sympy.Le: Le,
+            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 Expression.fromsympy(expr)
+        raise ValueError('non-domain expression: {!r}'.format(expr))

 
     def tosympy(self):
 
     def tosympy(self):

-        raise NotImplementedError
+        import sympy
+        polyhedra = [polyhedron.tosympy() for polyhedron in polyhedra]
+        return sympy.Or(*polyhedra)
+

 
 def And(*domains):
     if len(domains) == 0:
 
 def And(*domains):
     if len(domains) == 0: