如何写入现有的Excel文件而不覆盖数据（使用pandas）？
我使用pandas以下列方式写入excel文件：
import pandas
writer = pandas.ExcelWriter('Masterfile.xlsx')
data_filtered.to_excel(writer, "Main", cols=['Diff1', 'Diff2'])
writer.save()
Masterfile.xlsx已包含许多不同的选项卡。 但是，它还没有包含＆＃34; Main＆＃34;。
熊猫正确写入＆＃34; Main＆＃34; 不幸的是，它还会删除所有其他标签。
10个解决方案
111 votes
Pandas docs表示它将openpyxl用于xlsx文件。 快速浏览ExcelWriter中的代码，可以找出类似这样的信息：
import pandas
from openpyxl import load_workbook
book = load_workbook('Masterfile.xlsx')
writer = pandas.ExcelWriter('Masterfile.xlsx', engine='openpyxl')
writer.book = book
writer.sheets = dict((ws.title, ws) for ws in book.worksheets)
data_filtered.to_excel(writer, "Main", cols=['Diff1', 'Diff2'])
writer.save()
Ski answered -08-18T21:20:32Z
18 votes
这是一个辅助函数：
def append_df_to_excel(filename, df, sheet_name='Sheet1', startrow=None,
truncate_sheet=False,
**to_excel_kwargs):
"""
Append a DataFrame [df] to existing Excel file [filename]
into [sheet_name] Sheet.
If [filename] doesn't exist, then this function will create it.
Parameters:
filename : File path or existing ExcelWriter
(Example: '/path/to/file.xlsx')
df : dataframe to save to workbook
sheet_name : Name of sheet which will contain DataFrame.
(default: 'Sheet1')
startrow : upper left cell row to dump data frame.
Per default (startrow=None) calculate the last row
in the existing DF and write to the next row...
truncate_sheet : truncate (remove and recreate) [sheet_name]
before writing DataFrame to Excel file
to_excel_kwargs : arguments which will be passed to `DataFrame.to_excel()`
[can be dictionary]
Returns: None
"""
from openpyxl import load_workbook
import pandas as pd
# ignore [engine] parameter if it was passed
if 'engine' in to_excel_kwargs:
to_excel_kwargs.pop('engine')
writer = pd.ExcelWriter(filename, engine='openpyxl')
# Python 2.x: define [FileNotFoundError] exception if it doesn't exist
try:
FileNotFoundError
except NameError:
FileNotFoundError = IOError
try:
# try to open an existing workbook
writer.book = load_workbook(filename)
# get the last row in the existing Excel sheet
# if it was not specified explicitly
if startrow is None and sheet_name in writer.book.sheetnames:
startrow = writer.book[sheet_name].max_row
# truncate sheet
if truncate_sheet and sheet_name in writer.book.sheetnames:
# index of [sheet_name] sheet
idx = writer.book.sheetnames.index(sheet_name)
# remove [sheet_name]
writer.book.remove(writer.book.worksheets[idx])
# create an empty sheet [sheet_name] using old index
writer.book.create_sheet(sheet_name, idx)
# copy existing sheets
writer.sheets = {ws.title:ws for ws in writer.book.worksheets}
except FileNotFoundError:
# file does not exist yet, we will create it
pass
if startrow is None:
startrow = 0
# write out the new sheet
df.to_excel(writer, sheet_name, startrow=startrow, **to_excel_kwargs)
# save the workbook
writer.save()
注意：对于Pandas＆lt; 0.21.0，用sheetname替换sheet_name！
用法示例：
append_df_to_excel('d:/temp/test.xlsx', df)
append_df_to_excel('d:/temp/test.xlsx', df, header=None, index=False)
append_df_to_excel('d:/temp/test.xlsx', df, sheet_name='Sheet2', index=False)
append_df_to_excel('d:/temp/test.xlsx', df, sheet_name='Sheet2', index=False, startrow=25)
MaxU answered -08-18T21:21:05Z
12 votes
随着openpyxlversion 2.4.0和pandasversion 0.19.2，@ski提出的过程变得更简单：
import pandas
from openpyxl import load_workbook
with pandas.ExcelWriter('Masterfile.xlsx', engine='openpyxl') as writer:
writer.book = load_workbook('Masterfile.xlsx')
data_filtered.to_excel(writer, "Main", cols=['Diff1', 'Diff2'])
#That's it!
mvbentes answered -08-18T21:21:32Z
8 votes
老问题，但我猜有些人还在搜索这个 - 所以......
我发现这个方法很好，因为所有工作表都被加载到工作表的字典和数据帧对的字典中，由pandas使用sheetname = None选项创建。 在将电子表格读取为dict格式并将其从dict中写回之间添加，删除或修改工作表非常简单。 对我来说，xlsxwriter在速度和格式方面比openpyxl更适合这项特殊任务。
注意：未来版本的pandas（0.21.0+）将更改＆＃34; sheetname＆＃34; 参数到＆＃34; sheet_name＆＃34;。
# read a single or multi-sheet excel file
# (returns dict of sheetname(s), dataframe(s))
ws_dict = pd.read_excel(excel_file_path,
sheetname=None)
# all worksheets are accessible as dataframes.
# easy to change a worksheet as a dataframe:
mod_df = ws_dict['existing_worksheet']
# do work on mod_df...then reassign
ws_dict['existing_worksheet'] = mod_df
# add a dataframe to the workbook as a new worksheet with
# ws name, df as dict key, value:
ws_dict['new_worksheet'] = some_other_dataframe
# when done, write dictionary back to excel...
# xlsxwriter honors datetime and date formats
# (only included as example)...
with pd.ExcelWriter(excel_file_path,
engine='xlsxwriter',
datetime_format='yyyy-mm-dd',
date_format='yyyy-mm-dd') as writer:
for ws_name, df_sheet in ws_dict.items():
df_sheet.to_excel(writer, sheet_name=ws_name)
对于问题中的示例：
ws_dict = pd.read_excel('Masterfile.xlsx',
sheetname=None)
ws_dict['Main'] = data_filtered[['Diff1', 'Diff2']]
with pd.ExcelWriter('Masterfile.xlsx',
engine='xlsxwriter') as writer:
for ws_name, df_sheet in ws_dict.items():
df_sheet.to_excel(writer, sheet_name=ws_name)
b2002 answered -08-18T21:22:20Z
5 votes
我知道这是一个较旧的主题，但这是您在搜索时找到的第一个项目，如果您需要在已创建的工作簿中保留图表，则上述解决方案不起作用。 在这种情况下，xlwings是一个更好的选择 - 它允许您写入excel书并保留图表/图表数据。
简单的例子：
import xlwings as xw
import pandas as pd
#create DF
months = ['-01','-02','-03','-04','-05','-06','-07','-08','-09','-10','-11','-12']
value1 = [x * 5+5 for x in range(len(months))]
df = pd.DataFrame(value1, index = months, columns = ['value1'])
df['value2'] = df['value1']+5
df['value3'] = df['value2']+5
#load workbook that has a chart in it
wb = xw.Book('C:\\data\\bookwithChart.xlsx')
ws = wb.sheets['chartData']
ws.range('A1').options(index=False).value = df
wb = xw.Book('C:\\data\\bookwithChart_updated.xlsx')
xw.apps[0].quit()
flyingmeatball answered -08-18T21:22:48Z
3 votes
从pandas 0.24开始，您可以使用mode关键字参数ExcelWriter简化此操作：
import pandas as pd
with pd.ExcelWriter('the_file.xlsx', engine='openpyxl', mode='a') as writer:
data_filtered.to_excel(writer)
Will Ayd answered -08-18T21:23:14Z
1 votes
def append_sheet_to_master(self, master_file_path, current_file_path, sheet_name):
try:
master_book = load_workbook(master_file_path)
master_writer = pandas.ExcelWriter(master_file_path, engine='openpyxl')
master_writer.book = master_book
master_writer.sheets = dict((ws.title, ws) for ws in master_book.worksheets)
current_frames = pandas.ExcelFile(current_file_path).parse(pandas.ExcelFile(current_file_path).sheet_names[0],
header=None,
index_col=None)
current_frames.to_excel(master_writer, sheet_name, index=None, header=False)
master_writer.save()
except Exception as e:
raise e
这完全正常，只有主文件（我们添加新工作表的文件）的格式化丢失了。
Manish Mehra answered -08-18T21:23:41Z
0 votes
writer = pd.ExcelWriter('prueba1.xlsx'engine='openpyxl',keep_date_col=True)
＆＃34; keep_date_col＆＃34; 希望能帮助你
Edward answered -08-18T21:24:07Z
0 votes
book = load_workbook(xlsFilename)
writer = pd.ExcelWriter(self.xlsFilename)
writer.book = book
writer.sheets = dict((ws.title, ws) for ws in book.worksheets)
df.to_excel(writer, sheet_name=sheetName, index=False)
writer.save()
Pedro Machado answered -08-18T21:24:26Z
0 votes
在pandas 0.24中有一个更好的解决方案：
with pd.ExcelWriter(path, mode='a') as writer:
s.to_excel(writer, sheet_name='another sheet', index=False)
之前：
后：
所以现在升级你的熊猫：
pip install --upgrade pandas
blacksheep answered -08-18T21:25:02Z
