Coverage for sympy/polys/domains/pythonrationalfield.py : 22%

"""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 

@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