Add plot method
[linpy.git] / pypol / domains.py
index 20493fa..375be85 100644 (file)
@@ -2,10 +2,11 @@ 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
+from .linexprs import Expression, Symbol
 
 
 __all__ = [
@@ -50,7 +51,7 @@ class Domain:
         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):
@@ -138,12 +139,13 @@ class Domain:
         return self.complement()
 
     def simplify(self):
-        # see isl_set_coalesce, isl_set_detect_equalities,
-        # isl_set_remove_redundancies
-        # which ones? in which order?
-        raise NotImplementedError
+        #does not change anything in any of the examples
+        #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)
 
-    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
@@ -151,16 +153,35 @@ class Domain:
         islbset = libisl.isl_set_polyhedral_hull(islset)
         return Polyhedron._fromislbasicset(islbset, self.symbols)
 
-    def project(self, symbols):
-        # not sure what isl_set_project_out actually does…
-        # use isl_set_drop_constraints_involving_dims instead?
-        raise NotImplementedError
+    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))):
+            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):
-        from .polyhedra import Polyhedron
         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:
@@ -211,6 +232,92 @@ class Domain:
         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):
+        #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)
+
     @classmethod
     def _fromislset(cls, islset, symbols):
         from .polyhedra import Polyhedron
@@ -233,6 +340,7 @@ class Domain:
             self._dimension = len(self._symbols)
             return self
 
+    @classmethod
     def _toislset(cls, polyhedra, symbols):
         polyhedron = polyhedra[0]
         islbset = polyhedron._toislbasicset(polyhedron.equalities,
@@ -287,25 +395,34 @@ class Domain:
                 return Polyhedron(equalities, inequalities)
         raise SyntaxError('invalid syntax')
 
+    _RE_BRACES = re.compile(r'^\{\s*|\s*\}$')
+    _RE_EQ = re.compile(r'([^<=>])=([^<=>])')
+    _RE_AND = re.compile(r'\band\b|,|&&|/\\|∧|∩')
+    _RE_OR = re.compile(r'\bor\b|;|\|\||\\/|∨|∪')
+    _RE_NOT = re.compile(r'\bnot\b|!|¬')
+    _RE_NUM_VAR = Expression._RE_NUM_VAR
+    _RE_OPERATORS = re.compile(r'(&|\||~)')
+
     @classmethod
     def fromstring(cls, string):
-        # remove brackets
-        string = re.sub(r'^\{\s*|\s*\}$', '', string)
+        # remove curly brackets
+        string = cls._RE_BRACES.sub(r'', string)
         # replace '=' by '=='
-        string = re.sub(r'([^<=>])=([^<=>])', r'\1==\2', string)
+        string = cls._RE_EQ.sub(r'\1==\2', string)
         # replace 'and', 'or', 'not'
-        string = re.sub(r'\band\b|,|&&|/\\|∧|∩', r' & ', string)
-        string = re.sub(r'\bor\b|;|\|\||\\/|∨|∪', r' | ', string)
-        string = re.sub(r'\bnot\b|!|¬', r' ~', string)
-        tokens = re.split(r'(&|\||~)', string)
+        string = cls._RE_AND.sub(r' & ', string)
+        string = cls._RE_OR.sub(r' | ', string)
+        string = cls._RE_NOT.sub(r' ~', string)
+        # add implicit multiplication operators, e.g. '5x' -> '5*x'
+        string = cls._RE_NUM_VAR.sub(r'\1*\2', string)
+        # add parentheses to force precedence
+        tokens = cls._RE_OPERATORS.split(string)
         for i, token in enumerate(tokens):
             if i % 2 == 0:
-                # add implicit multiplication operators, e.g. '5x' -> '5*x'
-                token = re.sub(r'(\d+|\))\s*([^\W\d_]\w*|\()', r'\1*\2', token)
                 token = '({})'.format(token)
                 tokens[i] = token
         string = ''.join(tokens)
-        tree = ast.parse(string)
+        tree = ast.parse(string, 'eval')
         return cls._fromast(tree)
 
     def __repr__(self):
@@ -315,10 +432,25 @@ class Domain:
 
     @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):
-        raise NotImplementedError
+        import sympy
+        polyhedra = [polyhedron.tosympy() for polyhedron in polyhedra]
+        return sympy.Or(*polyhedra)
 
 
 def And(*domains):