'Return a b-spline representing the antiderivative.
Parameters
nu : int, optional
Antiderivative order. Default is 1.
Returns
b : BSpline object
A new instance representing the antiderivative.
Notes
If antiderivative is computed and ``self.extrapolate=\'periodic\'``,
it will be set to False for the returned instance. This is done because
the antiderivative is no longer periodic and its correct evaluation
outside of the initially given x interval is difficult.
See Also
splder, splantider'

def antiderivative(self, nu=1):

    c = self.c
    ct = (len(self.t) - len(c))
    if (ct > 0):
        c = np.r_[(c, np.zeros(((ct,) + c.shape[1:])))]
    tck = _fitpack_impl.splantider((self.t, c, self.k), nu)
    if (self.extrapolate == 'periodic'):
        extrapolate = False
    else:
        extrapolate = self.extrapolate
    return self.construct_fast(extrapolate=extrapolate, axis=self.axis, *tck)
