'Returns the cumulative distribution function evaluated at the support.
Notes
Will not work if fit has not been called.'

@cache_readonly
def cdf(self):

    _checkisfit(self)
    density = self.density
    kern = self.kernel
    if (kern.domain is None):
        (a, b) = ((- np.inf), np.inf)
    else:
        (a, b) = kern.domain
    func = (lambda x, s: kern.density(s, x))
    support = self.support
    support = np.r_[(a, support)]
    gridsize = len(support)
    endog = self.endog
    probs = [integrate.quad(func, support[(i - 1)], support[i], args=endog)[0] for i in range(1, gridsize)]
    return np.cumsum(probs)
