使用熊猫写入Excel工作表的日期错误

Question

I'm using the pandas.DataFrame.to_excel() function to write a few files loaded from databases into an Excel spreadsheet. The function being used is the following:

def country_reports(countries):
    writer = pd.ExcelWriter('country_reports.xlsx')
    for country in countries:
        df = report(country)
        df.to_excel(writer, country)
    writer.save()

The report(country) method just returns a DataFrame of relevant data for that country. I would like to run this report for multiple countries, and then have each country's data represented in its own tab in Excel. This would normally be pretty simple, but I have dates earlier than 1900 in some of my DataFrames, which makes it impossible for me to write to Excel, since it throws an error:

ValueError: Year not supported by Excel: 1861.

I had no issues when writing these files as CSVs, so I was curious if there would be some way to create an excel file that had multiple tabs represented by CSVs? If not, is there another way around this issue?

Answer 1

Do you just need the to show the dates in Excel? If that's the case, could you just convert to a string, something like this.

df['date_col'] = df['date_col'].apply(lambda x: x.date().isoformat())

If you actually need to work with dates in Excel, it's probably best to separate month / day / year into separate columns, something like this:

df['year'] = df['date_col'].apply(lambda x: x.year)
df['day'] = df['date_col'].apply(lambda x: x.day)
df['month'] = df['date_col'].apply(lambda x: x.month)