python - creating multiple excel worksheets using data in a pandas dataframe

Question

Just started using pandas and python.

I have a worksheet which I have read into a dataframe and the applied forward fill (ffill) method to.

I would then like to create a single excel document with two worksheets in it.

One worksheet would have the data in the dataframe before the ffill method is applied and the next would have the dataframe which has had the ffill method applied.

Eventually I intend to create one worksheet for every unique instance of data in a certain column of the dataframe.

I would then like to apply some vba formatting to the results - but i'm not sure which dll or addon or something I would need to call excel vba using python to format headings as bold and add color etc.

I've had partial success in that xlsxwriter will create a new workbook and add sheets, but dataframe.to_excel operations don't seems to work on the workbooks it creates, the workbooks open but the sheets are blank.

Thanks in advance.

import os
import time
import pandas as pd
import xlwt
from xlwt.Workbook import *
from pandas import ExcelWriter
import xlsxwriter

#set folder to import files from
path = r'path to some file'
#folder = os.listdir(path)

#for loop goes here

#get date
date = time.strftime('%Y-%m-%d',time.gmtime(os.path.getmtime(path)))

#import excel document
original = pd.DataFrame()
data = pd.DataFrame()

original = pd.read_excel(path,sheetname='Leave',skiprows=26)
data = pd.read_excel(path,sheetname='Leave',skiprows=26)

print (data.shape)
data.fillna(method='ffill',inplace=True)

#the code for creating the workbook and worksheets
wb= Workbook()
ws1 = wb.add_sheet('original')
ws2 = wb.add_sheet('result')
original.to_excel(writer,'original')
data.to_excel(writer,'result')
writer.save('final.xls')

Answer 1

Your sample code is almost correct except you need to create the writer object and you don't need to use the add_sheet() methods. The following should work:

# ...
writer = pd.ExcelWriter('final.xlsx')
data.to_excel(writer,'original')

# data.fillna() or similar.

data.to_excel(writer,'result')
writer.save()
# ...

The correct syntax for this is shown at the end of the Pandas DataFrame.to_excel() docs.

See also Working with Python Pandas and XlsxWriter.