Trouble wrting to Excel - python

I' am new to Python and trying to write into a merged cell within Excel. I can see the data that is already stored within this cell/row, so I know its there. However when I try to overwrite it nothing happens.
I have tried messing with the index and header as well but nothing seems to work.
import pandas as pd
from openpyxl import load_workbook
Read the excel file into a pandas DataFrame
df = pd.read_excel(file here', sheet_name='Sheet1')
print(df.iloc[8, 2])
Make the changes to the DataFrame
df.iloc[8, 2] = "Bob Smith"
Load the workbook
book = load_workbook(file here)
writer = pd.ExcelWriter(file here, engine='openpyxl')
writer.book = book
Write the DataFrame to the first sheet
df.to_excel(writer, index=False)
Save the changes to the Excel file
writer.save()

import pandas as pd
from openpyxl import *
file="C:/Users/OneDrive/Bureau/draftExcel.xlsx"
df = pd.read_excel(file,sheet_name='sheet1')
df.iat[5,0]='cell is updated'
print(df) # to check first in the terminal if the content of the cell is updated
book=load_workbook(file)
writer=pd.ExcelWriter(file, engine='openpyxl')
df.to_excel(writer,sheet_name='sheet1',index=False)
writer.close()
I tried to make an example from what you explained because you didn't show your code, so I hope it was helpful.
Instead of using .iloc I used .iat so you can update the data in a specific cell in your DataFrame using column_index instead of column_label.
Remember that the Excel file you are working on must be closed while you are editing data with python, if it is open you will get an error.

Related

Removing the Indexed Column when Merging 2 Excel Spreadsheets into a new Sheet in an existing Excel Spreadsheet using Pandas

I wanted to automate comparing two excel spreadsheets and updating old data (call this spreadsheet Old_Data.xlsx) with new data (from a different excel document; called New_Data.xlsx) and placing the updated data into a different sheet on on Old_Data.xlsx.
I am able to successfully create the new sheet in Old_Data.xlsx and see the changes between the two data sets, however, in the new sheet an index appears labeling the rows of data from 0-n. I've tried hiding this index so the information on each sheet in Old_Data.xlsx appears the same, however, I cannot successfully seem to get rid of the addition of the index. See the code below:
from openpyxl import load_workbook
# import xlwings as xl
import pandas as pd
import jinja2
# Load the workbook that is going to updated with new information.
wb = load_workbook('OldData.xlsx')
# Define the file path for all of the old and new data.
old_path = 'OldData.xlsx'
new_path = 'NewData.xlsx'
# Load the data frames for each Spreadsheet.
df_old = pd.read_excel(old_path)
print(df_old)
df_new = pd.read_excel(new_path)
print(df_new)
# Keep all original information why showing the differences in information and write
# to a new sheet in the workbook.
difference = pd.merge(df_old, df_new, how='right')
difference = difference.style.format.hide()
print(difference)
# Append the difference to an existing Excel File
with pd.ExcelWriter('OldData.xlsx', mode='a', engine='openpyxl', if_sheet_exists='replace') as writer:
difference.to_excel(writer, sheet_name="1-25-2023")
This is an image of the table of the second sheet that I creating. (https://i.stack.imgur.com/7Amdf.jpg)
I've tried adding the code:
difference = difference.style.format.hide
To get rid of the row, but I have not succeeded.
pass index = False as an argument in last line of you code. It should be something like this :-
with pd.ExcelWriter('OldData.xlsx', mode='a', engine='openpyxl', if_sheet_exists='replace') as writer:
difference.to_excel(writer, sheet_name="1-25-2023", index = False)
I think this should solve your problem.

Pandas partially removes contents of cells in random order

import pandas as pd
import openpyxl
df = pd.read_excel('file.xlsx', sheet_name='Лист1')
with pd.ExcelWriter('file.xlsx', engine="openpyxl", mode="a") as writer:
df.to_excel(writer, index=False, sheet_name='processing')
This code reads one sheet of an excel file and copies all the data to an adjacent sheet, but when searching for sheets, it turns out that some of the information is lost both in the original sheet and in the new sheet. Each time the code is executed, a different amount of information is overwritten.
But how is this possible? If there is a clear command in the code to read the first sheet - what makes it change? The same questions apply to writing a new sheet.
The screenshot below shows three different categories with symptoms:
enter image description here
I use versions: Pandas - 1.4.4, Openpyxl - 3.0.10
For example: it works well in pycharm, but it doesn't work in Jupyter notebook.
My suspicion is that the code somehow reacts incorrectly to the characters that are in the text (emoji) and this text with tags. In the initial version, there were many columns, but only one is problematic - which is in the example. But I am an amateur, and I only express my assumptions. I've run out of solutions.
Original file
Help me please. Best Regards.
My friend suggested this code, but it doesn't work either.
from html import unescape
from unicodedata import normalize
import pandas as pd
df = pd.read_excel(
'file.xlsx',
engine='openpyxl',
converters={
'Описание - Description': lambda x: normalize('NFKC', unescape(x))
}
)
with pd.ExcelWriter('file.xlsx', engine="openpyxl", mode="a") as writer:
df.to_excel(writer, index=False, sheet_name='processing')

Pandas dataframe to specific sheet in a excel file without losing formatting

I have a dataframe like as shown below
Date,cust,region,Abr,Number,
12/01/2010,Company_Name,Somecity,Chi,36,
12/02/2010,Company_Name,Someothercity,Nyc,156,
df = pd.read_clipboard(sep=',')
I would like to write this dataframe to a specific sheet (called temp_data) in the file output.xlsx
Therfore I tried the below
import pandas
from openpyxl import load_workbook
book = load_workbook('output.xlsx')
writer = pandas.ExcelWriter('output.xlsx', engine='openpyxl')
writer.book = book
writer.sheets = dict((ws.title, ws) for ws in book.worksheets)
I also tried the below
path = 'output.xlsx'
with pd.ExcelWriter(path) as writer:
writer.book = openpyxl.load_workbook(path)
final_df.to_excel(writer, sheet_name='temp_data',startrow=10)
writer.save()
But am not sure whether I am overcomplicating it. I get an error like as shown below. But I verifiedd in task manager, no excel file/task is running
BadZipFile: File is not a zip file
Moreover, I also lose my formatting of the output.xlsx file when I manage to write the file based on below suggestions. I already have a neatly formatted font,color file etc and just need to put the data inside.
Is there anyway to write the pandas dataframe to a specific sheet in an existing excel file? WITHOUT LOSING FORMATTING OF THE DESTIATION FILE
You need to just use to_excel from pandas dataframe.
Try below snippet:
df1.to_excel("output.xlsx",sheet_name='Sheet_name')
If there is existing data please try below snippet:
writer = pd.ExcelWriter('output.xlsx', engine='openpyxl')
# try to open an existing workbook
writer.book = load_workbook('output.xlsx')
df.to_excel(writer,index=False,header=False,startrow=len(reader)+1)
writer.save()
writer.close()
Are you restricted to using pandas or openpyxl?
Because if you're comfortable using other libraries, the easiest way is probably using win32com to puppet excel as if you were a user manually copying and pasting the information over.
import pandas as pd
import io
import win32com.client as win32
import os
csv_text = """Date,cust,region,Abr,Number
12/01/2010,Company_Name,Somecity,Chi,36
12/02/2010,Company_Name,Someothercity,Nyc,156"""
df = pd.read_csv(io.StringIO(csv_text),sep = ',')
temp_path = r"C:\Users\[User]\Desktop\temp.xlsx" #temporary location where to write this dataframe
df.to_excel(temp_path,index = False) #temporarily write this file to excel, change the output path as needed
excel = win32.Dispatch("Excel.Application")
excel.Visible = True #Switch these attributes to False if you'd prefer Excel to be invisible while excecuting this script
excel.ScreenUpdating = True
temp_wb = excel.Workbooks.Open(temp_path)
temp_ws = temp_wb.Sheets("Sheet1")
output_path = r"C:\Users\[User]\Desktop\output.xlsx" #Path to your output excel file
output_wb = excel.Workbooks.Open(output_path)
output_ws = output_wb.Sheets("Output_sheet")
temp_ws.Range('A1').CurrentRegion.Copy(Destination = output_ws.Range('A1')) # Feel free to modify the Cell where you'd like the data to be copied to
input('Check that output looks like you expected\n') # Added pause here to make sure script doesn't overwrite your file before you've looked at the output
temp_wb.Close()
output_wb.Close(True) #Close output workbook and save changes
excel.Quit() #Close excel
os.remove(temp_path) #Delete temporary excel file
Let me know if this achieves what you were after.
I spent all day on this (and a co-worker of mine spent even longer). Thankfully, it seems to work for my purposes - pasting a dataframe into an Excel sheet without changing any of the Excel source formatting. It requires the pywin32 package, which "drives" Excel as if it a user, using VBA.
import pandas as pd
from win32com import client
# Grab your source data any way you please - I'm defining it manually here:
df = pd.DataFrame([
['LOOK','','','','','','','',''],
['','MA!','','','','','','',''],
['','','I pasted','','','','','',''],
['','','','into','','','','',''],
['','','','','Excel','','','',''],
['','','','','','without','','',''],
['','','','','','','breaking','',''],
['','','','','','','','all the',''],
['','','','','','','','','FORMATTING!']
])
# Copy the df to clipboard, so we can later paste it as text.
df.to_clipboard(index=False, header=False)
excel_app = client.gencache.EnsureDispatch("Excel.Application") # Initialize instance
wb = excel_app.Workbooks.Open("Template.xlsx") # Load your (formatted) template workbook
ws = wb.Worksheets(1) # First worksheet becomes active - you could also refer to a sheet by name
ws.Range("A3").Select() # Only select a single cell using Excel nomenclature, otherwise this breaks
ws.PasteSpecial(Format='Unicode Text') # Paste as text
wb.SaveAs("Updated Template.xlsx") # Save our work
excel_app.Quit() # End the Excel instance
In general, when using the win32com approach, it's helpful to record yourself (with a macro) doing what you want to accomplish in Excel, then reading the generated macro code. Often this will give you excellent clues as to what commands you could invoke.
The solution to your problem exists here: How to save a new sheet in an existing excel file, using Pandas?
To add a new sheet from a df:
import pandas as pd
from openpyxl import load_workbook
import os
import numpy as np
os.chdir(r'C:\workdir')
path = 'output.xlsx'
book = load_workbook(path)
writer = pd.ExcelWriter(path, engine = 'openpyxl')
writer.book = book
### replace with your df ###
x = np.random.randn(100, 2)
df = pd.DataFrame(x)
df.to_excel(writer, sheet_name = 'x')
writer.save()
writer.close()
You can try xltpl.
Create a template file based on your output.xlsx file.
Render a file with your data.
from xltpl.writerx import BookWriterx
writer = BookWriterx('template.xlsx')
d = {'rows': df.values}
d['tpl_name'] = 'tpl_sheet'
d['sheet_name'] = 'temp_data'
writer.render_sheet(d)
d['tpl_name'] = 'other_sheet'
d['sheet_name'] = 'other'
writer.render_sheet(d)
writer.save('out.xls')
See examples.

Python: Write a dataframe to an already existing excel which contains a sheet with images

I have been working on this for too long now. I have an Excel with one sheet (sheetname = 'abc') with images in it and I want to have a Python script that writes a dataframe on a second separate sheet (sheetname = 'def') in the same excel file. Can anybody provide me with some example code, because everytime I try to write the dataframe, the first sheet with the images gets emptied.
This is what I tried:
book = load_workbook('filename_of_file_with_pictures_in_it.xlsx')
writer = pd.ExcelWriter('filename_of_file_with_pictures_in_it.xlsx', engine = 'openpyxl')
writer.book = book
x1 = np.random.randn(100, 2)
df = pd.DataFrame(x1)
df.to_excel(writer, sheet_name = 'def')
writer.save()
book.close()
It saves the random numbers in the sheet with the name 'def', but the first sheet 'abc' now becomes empty.
What goes wrong here? Hopefully somebody can help me with this.
Interesting question! With openpyxl you can easily add values, keep the formulas but cannot retain the graphs. Also with the latest version (2.5.4), graphs do not stay. So, I decided to address the issue with
xlwings :
import xlwings as xw
wb = xw.Book(r"filename_of_file_with_pictures_in_it.xlsx")
sht=wb.sheets.add('SheetMod')
sht.range('A1').value = np.random.randn(100, 2)
wb.save(r"path_new_file.xlsx")
With this snippet I managed to insert the random set of values and saved a new copy of the modified xlsx.As you insert the command, the excel file will automatically open showing you the new sheet- without changing the existing ones (graphs and formulas included). Make sure you install all the interdependencies to get xlwings to run in your system. Hope this helps!
You'll need to use an Excel 'reader' like Openpyxl or similar in combnination with Pandas for this, pandas' to_excel function is write only so it will not care what is inside the file when you open it.

How to write to an Excel sheet without exporting a dataframe first?

I am trying to write some text to a specific sheet in an Excel file. I export a number of pandas dataframes to the other tabs, but in this one I need only some text - basically some comments explaining how the other tabs were calculated.
I have tried this but it doesn't work:
import pandas as pd
writer=pd.ExcelWriter('myfile.xlsx')
writer.sheets['mytab'].write(1,1,'This is a test')
writer.close()
I have tried adding writer.book.add_worksheet('mytab') and
ws=writer.sheets['mytab']
ws.write(1,1,'This is a test')
but in all cases I am getting: keyerror:'mytab'.
The only solution I have found is to write an empty dataframe to the tab before writing my text to the same tab:
emptydf=pd.DataFrame()
emptydf['x']=[None]
emptydf.to_excel(writer,'mytab',header=False, index=False)
I could of course create a workbook instance, as in the example on the documentation of xlsxwriter: http://xlsxwriter.readthedocs.io/worksheet.html
However, my problem is that I already have a pd.ExcelWriter instance, which is used in the rest of my code to create the other excel sheets.
I even tried passing a workbook instance to to_excel(), but it doesn't work:
workbook = xlsxwriter.Workbook('filename.xlsx')
emptydf.to_excel(workbook,'mytab',header=False, index=False)
Is there any alternative to my solution of exporting an empty dataframe - which seems as unpythonic as it can get?
You mentioned that you used add_worksheet() method from the writer.book object, but it seems to work and do what you wanted it to do. Below I've put in a reproducible example that worked successfully.
import pandas as pd
print(pd.__version__)
writer = pd.ExcelWriter('test.xlsx', engine='xlsxwriter')
workbook = writer.book
ws = workbook.add_worksheet('mytab')
ws.write(1,1,'This is a test')
writer.close()
Thought I'd also mention that I'm using pandas 0.18.1.

Categories