将 DataFrame 列表保存到多表 Excel 电子表格

Question

How can I export a list of DataFrames into one Excel spreadsheet?
The docs for to_excel state:

Notes
If passing an existing ExcelWriter object, then the sheet will be added to the existing workbook. This can be used to save different DataFrames to one workbook

writer = ExcelWriter('output.xlsx')
df1.to_excel(writer, 'sheet1')
df2.to_excel(writer, 'sheet2')
writer.save()

Following this, I thought I could write a function which saves a list of DataFrames to one spreadsheet as follows:

from openpyxl.writer.excel import ExcelWriter
def save_xls(list_dfs, xls_path):
    writer = ExcelWriter(xls_path)
    for n, df in enumerate(list_dfs):
        df.to_excel(writer,'sheet%s' % n)
    writer.save()

However (with a list of two small DataFrames, each of which can save to_excel individually), an exception is raised (Edit: traceback removed) :

AttributeError: 'str' object has no attribute 'worksheets'

Presumably I am not calling ExcelWriter correctly, how should I be in order to do this?

Answer 1

You should be using pandas own ExcelWriter class:

from pandas import ExcelWriter
# from pandas.io.parsers import ExcelWriter

Then the save_xls function works as expected:

def save_xls(list_dfs, xls_path):
    with ExcelWriter(xls_path) as writer:
        for n, df in enumerate(list_dfs):
            df.to_excel(writer,'sheet%s' % n)
        writer.save()

Answer 2

In case anyone needs an example using a dictionary of dataframes:

from pandas import ExcelWriter

def save_xls(dict_df, path):
"""
Save a dictionary of dataframes to an excel file, with each dataframe as a separate page
"""

    writer = ExcelWriter(path)
    for key in dict_df:
        dict_df[key].to_excel(writer, key)

    writer.save()

example: save_xls(dict_df = my_dict, path = '~/my_path.xls')

Answer 3

Sometimes there can be issues(Writing an excel file containing unicode), if there are some non supporting character type in the data frame. To overcome it we can use ' xlsxwriter ' package as in below case:

for below code:

from pandas import ExcelWriter
import xlsxwriter
writer = ExcelWriter('notes.xlsx')
for key in dict_df:
        data[key].to_excel(writer, key,index=False)
writer.save()

I got the error as "IllegalCharacterError"

The code that worked:

%pip install xlsxwriter
from pandas import ExcelWriter
import xlsxwriter
writer = ExcelWriter('notes.xlsx')
for key in dict_df:
        data[key].to_excel(writer, key,index=False,engine='xlsxwriter')
writer.save()