Source code for sympy.polys.domains.pythonrationalfield

"""Implementation of :class:PythonRationalField class. """

from __future__ import print_function, division

from sympy.polys.domains.rationalfield import RationalField
from sympy.polys.domains.groundtypes import PythonInteger, PythonRational, SymPyRational

from sympy.polys.polyerrors import CoercionFailed
from sympy.utilities import public

[docs]@public class PythonRationalField(RationalField): """Rational field based on Python rational number type. """ dtype = PythonRational zero = dtype(0) one = dtype(1) alias = 'QQ_python' def __init__(self): pass def get_ring(self): """Returns ring associated with self. """ from sympy.polys.domains import PythonIntegerRing return PythonIntegerRing() def to_sympy(self, a): """Convert a to a SymPy object. """ return SymPyRational(a.numerator, a.denominator) def from_sympy(self, a): """Convert SymPy's Rational to dtype. """ if a.is_Rational: return PythonRational(a.p, a.q) elif a.is_Float: from sympy.polys.domains import RR p, q = RR.to_rational(a) return PythonRational(int(p), int(q)) else: raise CoercionFailed("expected Rational object, got %s" % a) def from_ZZ_python(K1, a, K0): """Convert a Python int object to dtype. """ return PythonRational(a) def from_QQ_python(K1, a, K0): """Convert a Python Fraction object to dtype. """ return a def from_ZZ_gmpy(K1, a, K0): """Convert a GMPY mpz object to dtype. """ return PythonRational(PythonInteger(a)) def from_QQ_gmpy(K1, a, K0): """Convert a GMPY mpq object to dtype. """ return PythonRational(PythonInteger(a.numer()), PythonInteger(a.denom())) def from_RealField(K1, a, K0): """Convert a mpmath mpf object to dtype. """ p, q = K0.to_rational(a) return PythonRational(int(p), int(q)) def numer(self, a): """Returns numerator of a. """ return a.numerator def denom(self, a): """Returns denominator of a. """ return a.denominator