def basis_element(self, x, i, d=0):

        x = np.asarray(x, np.float64)
        _shape = x.shape
        if _shape == ():
            x.shape = (1,)
        x.shape = (np.product(_shape,axis=0),)
        if i < self.tau.shape[0] - 1:
           ## TODO: OWNDATA flags...
            v = _hbspline.evaluate(x, self.tau, self.m, d, i, i+1)
        else:
            return np.zeros(x.shape, np.float64)

        if (i == self.tau.shape[0] - self.m):
            v = np.where(np.equal(x, self.tau[-1]), 1, v)
        v.shape = _shape
        return v
Evaluate a particular basis element of the BSpline,
dataset/ETHPy150Open statsmodels/statsmodels/statsmodels/sandbox/bspline.py/BSpline.basis_element