python - 如何检测时间序列中的翻转？

Question

对于在不同操作模式下运行的系统，我想减少模式之间的翻转。为此，需要检测翻转和校正。
假设我们有一个模式频繁切换的序列:

before = [0,0,0,(1,0),1,1,1,2,2,(1,2),1,1,1,(0,1),0]   # parenthesis indicate flipping

我想只在(改变点)进行交换以获得:

after  = [0,0,0,(0,1),1,1,1,2,2,(2,1),1,1,1,(1,0),0]   # parenthesis indicate corrections

我怎样才能做到这一点？

Answer 1

有一种“更简单”的方法可以找到范围 1 的翻转，但不适用于连续重复翻转

before = np.array([0,0,1,0,0,1,0,1,1,1,2,2,1,2,1,1,1,0,1,0,0])
goal = np.array(  [0,0,0,0,0,0,1,1,1,1,2,2,2,1,1,1,1,1,0,0,0])

diff = np.diff(before)          # find 'jumps' with range 1
diff[:-1][(diff == 0)[1:]] = 0  # correct 'right' side of 'jumps'
after = before - np.r_[0,diff]  # correct flipping

plt.plot(before, linestyle='--',label='before')
plt.plot(goal,   linestyle='-.',label='goal')
plt.plot(after,  linestyle=':', label='after')
plt.legend();

输出

适用于更大的步数和负“跳跃”

before = np.array([0,0,-1,0,0,1,0,1,1,1,4,4,1,4,1,1,1,0,1,0,0])
goal = np.array(  [0,0, 0,0,0,0,1,1,1,1,4,4,4,1,1,1,1,1,0,0,0])

diff = np.diff(before)          # find flipping with range 1
diff[:-1][(diff == 0)[1:]] = 0  # correct 'right' side of signal
after = before - np.r_[0,diff]  # correct flipping

plt.plot(before, linestyle='--',label='before')
plt.plot(goal,   linestyle='-.',label='goal')
plt.plot(after,  linestyle=':', label='after')
plt.legend();

输出


解决方案的局限性

连续重复翻转

    before = [0,1,0,1,0,1,1,1,1]
    goal   = [0,0,0,0,1,1,1,1,1]