'Find nearest neighbour interpolated y_new = f(x_new).'

def _call_nearest(self, x_new):

    x_new_indices = searchsorted(self.x_bds, x_new, side='left')
    x_new_indices = x_new_indices.clip(0, (len(self.x) - 1)).astype(intp)
    y_new = self._y[x_new_indices]
    return y_new
