Doctest fail on numparam.reflective_correlation (numerical precision)

[galenseilis]

Here is the doctest example:

    Examples
    --------
    >>> F = [lambda x,y: x+y for i in range(2)]
    >>> I = [(0,1)]*2
    >>> reflective_correlation(F, I)
    1.0

And here is the result:

>>> numparam.reflective_correlation(F, I)
1.0000000000000002