如何在不替换现有数据的情况下使用 pandas 将结果写回 csv 文件？

Question

I am trying to read the file, then i would like to done the calculation to write back to the same file. But the result will replace the ori existing data, how can i change it? Please help me

import pandas as pd

df = pd.read_csv(r'C:\Users\Asus\Downloads\Number of Employed Persons by Status In Employment, Malaysia.csv')

print(df.to_string())

mean1 = df['Value'].mean()
sum1 = df['Value'].sum()

print ('Mean Value: ' + str(mean1))
print ('Sum of Value: ' + str(sum1))

df = pd.DataFrame([['Mean Value: ' + str(mean1)], ['Sum of Value: ' + str(sum1)]])

df.to_csv(r'C:\Users\Asus\Downloads\Number of Employed Persons by Status In Employment, Malaysia.csv', index=False)

print(df)

Answer 1

Do you want to add the data at the bottom of the file?

Override the data is not the best approach, in my opinion, but this is one solution:

import pandas as pd

df = pd.read_csv('data.csv')

mean1 = df['Value'].mean() 
sum1 = df['Value'].sum()

df.loc[df.index.max() + 1] = ['Mean','Sum']
df.loc[df.index.max() + 1] = [mean1, sum1]

df.to_csv('data.csv', index=False)

Another option could be: Save all into an xlsx at the end (is better load the data from CSV if there is a large of data) and keep the dataframe1 in a first sheet, and the analysis on a second sheet.