我有一个数组:
import numpy as np
# Create an array of values
values = np.array([41,17,44,36,14,29,33,38,49,39,22,15,46])
# Calculate the mean
mean = np.mean(values)
# Calculate the standard deviation
standard_deviation = np.std(values)
如何计算平均值和第一个标准差之间的平均值?我有:
# Calculate the average of values between the mean and the first standard deviation
mean_between_mean_and_first_standard_deviation = np.mean(values[(values >= mean) & (values <= standard_deviation)])
print("Average between mean and first standard deviation:", mean_between_mean_and_first_standard_deviation)
我得到:
Average between mean and first standard deviation: nan
2条答案
按热度按时间2guxujil1#
下面的图表应该会更清楚。您需要选择介于
mean
和mean
之间的值加上standard_deviation
的一倍。或者如果你想要中间点,你可以这样做:
wqsoz72f2#
例如,您可以这样做:
values >= mean
的计算结果是一个与values
形状相同的布尔数组,因此它在满足条件的任何地方都有True
,否则有False
。同样,对于values <= mean+standard_deviation
。剩下的就是使用
np.logical_and()
来找到满足这两个条件的地方。然后使用此布尔数组计算values
的平均值,仅在值满足两个条件的索引处