data_list
和monthly_values
数组相互关联,因此数据点'2019-09-01 00:00:00'= 15 , 2019-10-01 00:00:00'= 39.6... etc
。下面的 year_changes
函数显示了发生新年的索引。 .因此,由于 2019 年有 4 个月 2019-09-01 00:00:00 - 2020-01-01 00:00:00
,因此它取数字 15., 39.6, 0.2, 34.3
的总和并除以 2019 年的月份数,即 4,结果 Expected Output
1}}。但我试图制作一个图表来显示 22.28
我如何能够编写这样的代码?
mean, median, max ,min
输出:
import numpy as np
import pandas as pd
from pandas import DataFrame
date_list = ['2019-09-01 00:00:00', '2019-10-01 00:00:00', '2019-11-01 00:00:00',
'2019-12-01 00:00:00', '2020-01-01 00:00:00', '2020-02-01 00:00:00',
'2020-03-01 00:00:00', '2020-04-01 00:00:00', '2020-05-01 00:00:00',
'2020-06-01 00:00:00', '2020-07-01 00:00:00', '2020-08-01 00:00:00',
'2020-09-01 00:00:00','2020-10-01 00:00:00', '2020-11-01 00:00:00',
'2020-12-01 00:00:00','2021-01-01 00:00:00','2021-02-01 00:00:00', '2021-03-01 00:00:00',
'2021-04-01 00:00:00','2021-05-01 00:00:00', '2021-06-01 00:00:00',
'2021-07-01 00:00:00']
monthly_values = np.array([ 15., 39.6, 0.2, 34.3, 19.6, 26.8, 15.7, 26., 12.6, 15.5, 18.6, 2.3, 6.5,
2.5, 12.2, 11.6, 93.9, 25.5, 26.5, -16.5, -1.4, -1.8, 5.])
data = pd.DataFrame({"Date": date_list, "Averages": monthly_values})
data["Date"] = pd.to_datetime(data["Date"])
print(data.groupby(data["Date"].dt.year).mean())
预期输出:
Averages
Date
2019 22.275000
2020 14.158333
2021 18.742857
答案 0 :(得分:0)
通过 groupby()
、agg()
、droplevel()
和 rename()
尝试:
out=(data.groupby(data["Date"].dt.year)
.agg(['mean','median','max','min'])
.droplevel(0,1)
.rename(columns=lambda x:'Average' if x=='mean' else x.title()))
或
通过 pivot_table()
、droplevel()
和 rename()
:
out=(data.pivot_table('Averages',data["Date"].dt.year,aggfunc=['mean','median','max','min'])
.droplevel(1,1)
.rename(columns=lambda x:'Average' if x=='mean' else x.title()))
out
的输出:
Average Median Max Min
Date
2019 22.275000 24.65 39.6 0.2
2020 14.158333 14.05 26.8 2.3
2021 18.742857 5.00 93.9 -16.5