+import ctypes, ctypes.util
import functools
import numbers
-import ctypes, ctypes.util
from fractions import Fraction, gcd
from . import isl, islhelper
+from .isl import libisl, Context, BasicSet
-libisl = ctypes.CDLL(ctypes.util.find_library('isl'))
-
-libisl.isl_printer_get_str.restype = ctypes.c_char_p
-
__all__ = [
'Expression',
'constant', 'symbol', 'symbols',
'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)
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
-
-
-
class Expression:
"""
__getitem__ = coefficient
+ @property
def coefficients(self):
for symbol in self.symbols():
yield symbol, self.coefficient(symbol)
return self.coefficient(symbol)
return int(self.constant)
-
def symbol(self):
if not self.issymbol():
raise ValueError('not a symbol: {}'.format(self))
@_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:
@_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:
@_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
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)
@_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))
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):
def isconstant(self):
return len(self._coefficients) == 0
-
def isempty(self):
return bool(libisl.isl_basic_set_is_empty(self._bset))
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):
else:
return True
-
def __contains__(self, value):
# is the value in the polyhedron?
raise NotImplementedError
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):
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)
+ ctx = Context()
+ space = libisl.isl_space_set_alloc(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, islhelper.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, islhelper.isl_dim_set, iden, num) #use 3 for type isl_dim_set
+ bset = libisl.isl_basic_set_add_constraint(bset, cin)
+ bset = 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)