Return True if x < y or x > y and False otherwise.

    This function returns False whenever x and/or y is a NaN.

def lessgreater(x, y):
    """
    Return True if x < y or x > y and False otherwise.

    This function returns False whenever x and/or y is a NaN.

    """
    x = BigFloat._implicit_convert(x)
    y = BigFloat._implicit_convert(y)
    return mpfr.mpfr_lessgreater_p(x, y)