pandas根据dataframe生成一个excel文件：

Dataframe保存新文件

直接把dataframe格式的数据保存到多个sheet页程序如下：

excel_file = "导出excel文件.xlsx"
if os.path.exists(excel_file):
    os.remove(excel_file)

# 生成一个新文件
with pd.ExcelWriter(excel_file) as writer:
    pd.DataFrame(np.random.random(size=(5, 5))).to_excel(writer, sheet_name="sheet1")
    pd.DataFrame(np.random.random(size=(5, 5))).to_excel(writer, sheet_name="sheet2")
    pd.DataFrame(np.random.random(size=(5, 5))).to_excel(writer, sheet_name="sheet3")

追加写入：

首先需要指定使用openpyxl，然后使用pd.ExcelWriter(excel_file, engine='openpyxl', mode='a')打开文件，在文件中直接追加即可：

with pd.ExcelWriter(excel_file, engine='openpyxl', mode='a') as writer:
    pd.DataFrame(np.random.random(size=(5, 5))).to_excel(writer, sheet_name="追加sheet1")
    pd.DataFrame(np.random.random(size=(5, 5))).to_excel(writer, sheet_name="追加sheet2")

完整示例

import pandas as pd
import numpy as np
import os


def main():
    excel_file = "导出excel文件.xlsx"
    if os.path.exists(excel_file):
        os.remove(excel_file)
   
    # 生成一个新文件
    with pd.ExcelWriter(excel_file) as writer:
        pd.DataFrame(np.random.random(size=(5, 5))).to_excel(writer, sheet_name="sheet1")
        pd.DataFrame(np.random.random(size=(5, 5))).to_excel(writer, sheet_name="sheet2")
        pd.DataFrame(np.random.random(size=(5, 5))).to_excel(writer, sheet_name="sheet3")
    
    # 在已有的文件中添加
    with pd.ExcelWriter(excel_file, engine='openpyxl', mode='a') as writer:
        pd.DataFrame(np.random.random(size=(5, 5))).to_excel(writer, sheet_name="追加sheet1")
        pd.DataFrame(np.random.random(size=(5, 5))).to_excel(writer, sheet_name="追加sheet2")


if __name__ == '__main__':
    main()