gp_utils.py 文件源码

def breakpoint_linear(x, ts, k1, k2, c1):
    '''Function representing a step-wise linear curve with one
    breakpoint located at ts.
    '''
    return np.piecewise(x, [x < ts], [lambda x: k1 * x + c1,
                                      lambda x: k2 * x + (k1 - k2) * ts + c1])