给出如下数组:
array([ 33.5 , -12.17, -1.58, -6.15, 4.73, -5.62, -5.59, -0.79,
-4.73, 0.58, 1.07, -1.33, 1.22, 2.72, -3.24, -3.33,
0.65, 0.79, 2.66, -1.45, 2. , 3.52, -0.6 , 1.36,
-0.51, -1.25, -0.37, 0.55, 2.01, -0.25, 0.08, -0.38,
0.94, 0.4 , -1.15, -1.2 , -1.11, 1.33, -1.11, 1.02,
-0.55, 0.59, -0.8 , -0.28, -0.61, 0.48, -1.94, 0.14,
-0.79, -1.34, 0.46, 0.69, -0.08, -0.2 , 0.16, -1.42,
-0.29, -0.48, -0.03, -0.03, -0.39, 0.74, 0.04, 0.5 ,
0.2 , 0.09, 1.53, -0.98, 0.22, 0.86, -0.05, 0.06,
0.08, -0.69, -0.54, -0.77, 0.35, 0.45, -0.16, -0.07,
-0.32, 1.01, 0.21, -0.24, 0.06, -0.54, -0.2 , -0.36,
0.27, 0.36, 0.16, -0.29, 0.04, -0.53, 0.46, 0.37,
0.14, -0.41, 0.3 , -0.09, -0.49, -0.26, -0.16, -0.33,
-0.03, -0.46, 0.14, 0.01, -0.41, 0.29, -0.17, -0.16,
-0.09, 0.1 , 0.04, -0.08, -0.33, -0.06, -0.09, -0.21,
0.06, -0.31, -0.23, -0.15, 0.02, -0.11, -0.49, 0.22,
0.49, -0.22, 0.07, -0.02, -0.07, -0.47, -0.22, -0.13,
0.22, 0.23, 0.17, -0.18, -0.09, -0.22, -0.29, 0.19,
0.01, 0.13, 0.22, -0.29, 0.01, -0.11, -0.33, 0.1 ,
0.1 , 0.14, -0.09, -0.33, -0.01, 0.29, 0.07, 0.1 ,
0.09, 0.24, -0.07, 0.2 , -0.13, -0.04, -0.39, -0.12,
-0.27, 0.01, 0.12, 0.05, -0.02, -0.1 , 0.21, -0.13,
-0.02, -0.11, -0.03, -0.19, 0.16, 0.14, 0.06, -0.12,
0.04, -0.47, -0.06, 0.2 , 0.13, 0.11, -0.17, -0.14,
-0.02, -0.33, -0.21, -0.22, -0.1 , 2.72, 0.03, -0.09,
0.03, -0.07, -0.14, -0.03, -0.16, 0.03, -0.08, 0.02,
0.04, -0.1 , -0.04, -0.05, 0.13, -0.39, 0.01, -0.16,
0.2 , 0.13, -0.24, -0.27, -0.08, -0.62, -0.04, -0.31,
0.02, 0.25, 0.23, 0.05, -0.12, -0.02, 0.1 , -0.02,
-0.09, 0.27, -0.14, 0.15, -0.14, 0.03, -0.13, -0.09,
-0.12, -0.07, -0.1 , 0.06, -0.13, -0.05, -0.07, -0.17,
-0.03, -0. , 0.25, 0.1 , 0.06, 0.16, -0.01, 0.28,
0. , -0.07, 0.19, 0.24, 0.02, 0.09, -0.05, -0.06,
-0.05, 0.08, -0.01, 0.05, -0.12, -0. , 0.01, -0.13,
-0.1 , 0.05, -0.18, -0.13, 0.3 , 0.21, 0.17, -0.09,
0.21, -0.02, -0.04, 0.14, 0.22, -0.09, -0.04, 0.08,
0.15, -0.08, 0.04, -0.07, -0.1 , 0.01, 0.04, -0.01,
0.06, 0.01, 0.27, -0.02, 0.07, -0.02, 0.22, 0.11,
-0.03, 0.16, 0.03, -0.19, 0.16, 0.05, -0.08, 0.07,
0.03, -0.17, 0.13, 0.13, 0.13, -0.12, -0.16, -0.16,
0.06, 0.2 , -0.07, -0.1 , -0.05, -0.17, 0.02, 0.13,
-0.04, -0.07, -0.17, -0.18, 0.03, -0.17, -0.07, 0.12,
-0.05, -0. , -0. , 0.14, -0.13, 0.03])
我想找到数组没有波动的索引,或者说考虑下一项不再重要。
我如何确定这一点?例如,有没有一种方法可以用熊猫来计算?也许考虑总平均值并检查在计算中添加额外的项目是否会明显增加或减少总平均值?
我试图找到本地的最小值和最大值
extrema = np.concatenate((argrelmin(array)[0], argrelmax(array)[0]))
但是基本上返回整个数组的长度,因为数组仍然有波动
您可以通过使用滑动窗口并查看窗口上的标准偏差来进行评估。一个简单的阈值可能就足够了。例如:
k = 6 # window size
thresh = 0.5
for i in range(0, len(a) - k):
b = np.std(a[i:i+k])
if b < thresh:
print(i)
break
>>> 55