Rename islhelper into _isl
[linpy.git] / pypol / linear.py
index be30fad..8e96f35 100644 (file)
@@ -1,14 +1,12 @@
+import ctypes, ctypes.util
 import functools
 import numbers
-import json
-import ctypes, ctypes.util
-from pypol import isl, islhelper
 
 from fractions import Fraction, gcd
 
-libisl = ctypes.CDLL(ctypes.util.find_library('isl'))
+from . import isl
+from .isl import libisl
 
-libisl.isl_printer_get_str.restype = ctypes.c_char_p
 
 __all__ = [
     'Expression',
@@ -18,28 +16,6 @@ __all__ = [
     'empty', 'universe'
 ]
 
-'''
-def symbolToInt(self):
-     make dictionary of key:value (letter:integer)
-        iterate through the dictionary to find matching symbol
-        return the given integer value
-    d = {'a': 1, 'b': 2, 'c': 3, 'd': 4, 'e': 5, 'f': 6, 'g': 7, 'h': 8, 'i': 6, 'j': 10, 'k': 11, 'l': 12, 'm': 13, 'n': 14,
-         'o': 15, 'p': 16, 'q': 17, 'r': 18, 's': 19, 't': 20, 'u': 21, 'v': 22, 'w': 23, 'x': 24, 'y': 25, 'z': 26}
-    if self in d:
-        num = d.get(self)
-    return num
-'''
-
-ids = {}
-
-def get_ids(co):
-    if co in ids:
-        return ids.get(co)
-    else:
-        idd = len(ids)
-        ids[co] = idd
-        print(ids)
-        return idd
 
 def _polymorphic_method(func):
     @functools.wraps(func)
@@ -65,27 +41,8 @@ def _polymorphic_operator(func):
         raise TypeError('arguments must be linear expressions')
     return wrapper
 
-class Context:
-
-    __slots__ = ('_ic')
-
-    def __init__(self):
-        self._ic = libisl.isl_ctx_alloc()
-
-    @property
-    def _as_parameter_(self):
-        return self._ic
-
-    #comment out so does not delete itself after being created
-    #def __del__(self):
-    #   libisl.isl_ctx_free(self)
-
-    def __eq__(self, other):
-        if not isinstance(other, Context):
-            return False
-        return self._ic == other._ic
-
 
+_main_ctx = isl.Context()
 
 
 class Expression:
@@ -137,6 +94,7 @@ class Expression:
 
     __getitem__ = coefficient
 
+    @property
     def coefficients(self):
         for symbol in self.symbols():
             yield symbol, self.coefficient(symbol)
@@ -158,7 +116,6 @@ class Expression:
             return self.coefficient(symbol)
         return int(self.constant)
 
-
     def symbol(self):
         if not self.issymbol():
             raise ValueError('not a symbol: {}'.format(self))
@@ -179,8 +136,8 @@ class Expression:
 
     @_polymorphic_method
     def __add__(self, other):
-        coefficients = dict(self.coefficients())
-        for symbol, coefficient in other.coefficients():
+        coefficients = dict(self.coefficients)
+        for symbol, coefficient in other.coefficients:
             if symbol in coefficients:
                 coefficients[symbol] += coefficient
             else:
@@ -192,8 +149,8 @@ class Expression:
 
     @_polymorphic_method
     def __sub__(self, other):
-        coefficients = dict(self.coefficients())
-        for symbol, coefficient in other.coefficients():
+        coefficients = dict(self.coefficients)
+        for symbol, coefficient in other.coefficients:
             if symbol in coefficients:
                 coefficients[symbol] -= coefficient
             else:
@@ -207,7 +164,7 @@ class Expression:
     @_polymorphic_method
     def __mul__(self, other):
         if other.isconstant():
-            coefficients = dict(self.coefficients())
+            coefficients = dict(self.coefficients)
             for symbol in coefficients:
                 coefficients[symbol] *= other.constant
             constant = self.constant * other.constant
@@ -290,7 +247,7 @@ class Expression:
 
     def __repr__(self):
         string = '{}({{'.format(self.__class__.__name__)
-        for i, (symbol, coefficient) in enumerate(self.coefficients()):
+        for i, (symbol, coefficient) in enumerate(self.coefficients):
             if i != 0:
                 string += ', '
             string += '{!r}: {!r}'.format(symbol, coefficient)
@@ -323,24 +280,24 @@ class Expression:
 
     @_polymorphic_method
     def __le__(self, other):
-        return Polyhedron(inequalities=[(self - other)._canonify()])
+        return Polyhedron(inequalities=[(other - self)._canonify()])
 
     @_polymorphic_method
     def __lt__(self, other):
-        return Polyhedron(inequalities=[(self - other)._canonify() + 1])
+        return Polyhedron(inequalities=[(other - self)._canonify() - 1])
 
     @_polymorphic_method
     def __ge__(self, other):
-        return Polyhedron(inequalities=[(other - self)._canonify()])
+        return Polyhedron(inequalities=[(self - other)._canonify()])
 
     @_polymorphic_method
     def __gt__(self, other):
-        return Polyhedron(inequalities=[(other - self)._canonify() + 1])
+        return Polyhedron(inequalities=[(self - other)._canonify() - 1])
 
 
 def constant(numerator=0, denominator=None):
     if denominator is None and isinstance(numerator, numbers.Rational):
-        return Expression(constant=3)
+        return Expression(constant=numerator)
     else:
         return Expression(constant=Fraction(numerator, denominator))
 
@@ -403,14 +360,7 @@ class Polyhedron:
                         raise TypeError('non-integer constraint: '
                                 '{} <= 0'.format(constraint))
                 self._inequalities.append(constraint)
-        self._bset = self.to_isl()
-        #print(self._bset)
-        #put this here just to test from isl method
-        #from_isl = self.from_isl(self._bset)
-        #print(from_isl)
-        #rint(self)
-        return self._bset
-
+        return self
 
     @property
     def equalities(self):
@@ -427,7 +377,6 @@ class Polyhedron:
     def isconstant(self):
         return len(self._coefficients) == 0
 
-
     def isempty(self):
         return bool(libisl.isl_basic_set_is_empty(self._bset))
 
@@ -435,12 +384,11 @@ class Polyhedron:
         yield from self.equalities
         yield from self.inequalities
 
-
     def symbols(self):
         s = set()
         for constraint in self.constraints():
-            s.update(constraint.symbols)
-            yield from sorted(s)
+            s.update(constraint.symbols())
+        return sorted(s)
 
     @property
     def dimension(self):
@@ -453,7 +401,6 @@ class Polyhedron:
         else:
             return True
 
-
     def __contains__(self, value):
         # is the value in the polyhedron?
         raise NotImplementedError
@@ -531,7 +478,7 @@ class Polyhedron:
         for constraint in self.equalities:
             constraints.append('{} == 0'.format(constraint))
         for constraint in self.inequalities:
-            constraints.append('{} <= 0'.format(constraint))
+            constraints.append('{} >= 0'.format(constraint))
         return '{{{}}}'.format(', '.join(constraints))
 
     def __repr__(self):
@@ -544,57 +491,67 @@ class Polyhedron:
     def fromstring(cls, string):
         raise NotImplementedError
 
-    def to_isl(self):
-        #d = Expression().__dict__  #write expression values to dictionary in form {'_constant': value, '_coefficients': value}
-        d = {'_constant': 2, '_coefficients': {'b':1}}
-        coeff = d.get('_coefficients')
-        num_coefficients = len(coeff)
-        space = libisl.isl_space_set_alloc(Context(), 0, num_coefficients)
-        bset = libisl.isl_basic_set_empty(libisl.isl_space_copy(space))
-        ls = libisl.isl_local_space_from_space(libisl.isl_space_copy(space))
+    def _symbolunion(self, *others):
+        symbols = set(self.symbols())
+        for other in others:
+            symbols.update(other.symbols())
+        return sorted(symbols)
+
+    def _to_isl(self, symbols=None):
+        if symbols is None:
+            symbols = self.symbols()
+        num_coefficients = len(symbols)
+        space = libisl.isl_space_set_alloc(_main_ctx, 0, num_coefficients)
+        bset = libisl.isl_basic_set_universe(libisl.isl_space_copy(space))
+        ls = libisl.isl_local_space_from_space(space)
         ceq = libisl.isl_equality_alloc(libisl.isl_local_space_copy(ls))
         cin = libisl.isl_inequality_alloc(libisl.isl_local_space_copy(ls))
-        '''if there are equalities/inequalities, take each constant and coefficient and add as a constraint to the basic set
-        need to change the symbols method to a lookup table for the integer value for each letter that could be a symbol'''
-        if self._equalities:
-            if '_constant' in d:
-                value = d.get('_constant')
-                ceq = libisl.isl_constraint_set_constant_si(ceq, value)
-            if '_coefficients' in d:
-                value_co = d.get('_coefficients')
-                for co in value_co:
-                    num = value_co.get(co)
-                    ceq = libisl.isl_constraint_set_coefficient_si(ceq, islhelper.isl_dim_set, get_ids(co), num)
-            bset = libisl.isl_set_add_constraint(bset, ceq)
-
-        if self._inequalities:
-            if '_constant' in d:
-                value = d.get('_constant')
-                cin = libisl.isl_constraint_set_constant_si(cin, value)
-            if '_coefficients' in d:
-                value_co = d.get('_coefficients')
-                for co in value_co:
-                    num = value_co.get(co)
-                    if value_co: #if dictionary not empty add coefficient as to constraint
-                        cin = libisl.isl_constraint_set_coefficient_si(cin, islhelper.isl_dim_set, get_ids(co), num)
-            bset = libisl.isl_set_add_constraint(bset, cin)
-        ip = libisl.isl_printer_to_str(Context()) #create string printer
-        ip = libisl.isl_printer_print_set(ip, bset) #print set to printer
-        string = libisl.isl_printer_get_str(ip)   #get string from printer
-        string = str(string)
-        print(string)
-        return string
-
+        '''if there are equalities/inequalities, take each constant and coefficient and add as a constraint to the basic set'''
+        if list(self.equalities): #check if any equalities exist
+            for eq in self.equalities:
+                coeff_eq = dict(eq.coefficients)
+                if eq.constant:
+                    value = eq.constant
+                    ceq = libisl.isl_constraint_set_constant_si(ceq, value)
+                for eq in coeff_eq:
+                    num = coeff_eq.get(eq)
+                    iden = symbols.index(eq)
+                    ceq = libisl.isl_constraint_set_coefficient_si(ceq, libisl.isl_dim_set, iden, num)  #use 3 for type isl_dim_set
+            bset = libisl.isl_basic_set_add_constraint(bset, ceq)
+        if list(self.inequalities): #check if any inequalities exist
+            for ineq in self.inequalities:
+                coeff_in = dict(ineq.coefficients)
+                if ineq.constant:
+                    value = ineq.constant
+                    cin = libisl.isl_constraint_set_constant_si(cin, value)
+                for ineq in coeff_in:
+                    num = coeff_in.get(ineq)
+                    iden = symbols.index(ineq)
+                    cin = libisl.isl_constraint_set_coefficient_si(cin, libisl.isl_dim_set, iden, num)  #use 3 for type isl_dim_set
+            bset = libisl.isl_basic_set_add_constraint(bset, cin)
+        bset = isl.BasicSet(bset)
+        return bset
 
     def from_isl(self, bset):
         '''takes basic set in isl form and puts back into python version of polyhedron
-        isl example code gives idl form as:
-            "{[i] : exists (a : i = 2a and i >= 10 and i <= 42)}");'''
-
-        poly = 0
-        return poly
-
-empty = eq(1,1)
-
-
-universe = Polyhedron()
+        isl example code gives isl form as:
+            "{[i] : exists (a : i = 2a and i >= 10 and i <= 42)}")
+            our printer is giving form as:
+            b'{ [i0] : 1 = 0 }' '''
+        #bset = self
+        if self._equalities:
+            constraints = libisl.isl_basic_set_equalities_matrix(bset, 3)
+        elif self._inequalities:
+            constraints = libisl.isl_basic_set_inequalities_matrix(bset, 3)
+        print(constraints)
+        return constraints
+
+empty = None #eq(0,1)
+universe = None #Polyhedron()
+
+if __name__ == '__main__':
+    ex1 = Expression(coefficients={'a': 1, 'x': 2}, constant=2)
+    ex2 = Expression(coefficients={'a': 3  , 'b': 2}, constant=3)
+    p = Polyhedron(inequalities=[ex1, ex2])
+    bs = p._to_isl()
+    print(bs)