(expr)
return expr in [S.NaN, S.Infinity, S.NegativeInfinity, S.ComplexInfinity]
Do not treat NaN and infinities as valid polynomial coefficients.
Do not treat NaN and infinities as valid polynomial coefficients.
Do not treat NaN and infinities as valid polynomial coefficients .
def _not_a_coeff(expr):
    """Do not treat NaN and infinities as valid polynomial coefficients. """
    return expr in [S.NaN, S.Infinity, S.NegativeInfinity, S.ComplexInfinity]
def _not_a_coeff ( expr ) : return expr in [ S . NaN , S . Infinity , S . NegativeInfinity , S . ComplexInfinity ]