How to put a value to an excel cell? - python

You'll probably laugh at me, but I am sitting on this for two weeks. I'm using python with pandas.
All I want to do, is to put a calculated value in a pre-existing excel file to a specific cell without changing the rest of the file. That's it.
Openpyxl makes my file unusable (means, I can not open because it's "corrupted" or something) or it plainly delets the whole content of the file. Xlsxwriter cannot read or modify pre-existing files. So it has to be pandas.
And for some reason I can't use worksheet = writer.sheets['Sheet1'], because that leads to an "unhandled exception".
Guys. Help.

I tried a bunch of packages but (for a lot of reasons) I ended up using xlwings. You can do pretty much anything with it in python that you can do in Excel.
Documentation link
So with xlwings you'd have:
import xlwings as xw
# open app_excel
app_excel = xw.App(visible = False)
# open excel template
wbk = xw.Book( r'stuff.xlsx' )
# write to a cell
wbk.sheets['Sheet1'].range('B5').value = 15
# save in the same place with the same name or not
wbk.save()
wbk.save( r'things.xlsx' )
# kill the app_excel
app_excel.kill()
del app_excel
Let me know how it goes.

Related

Why is openpyxl keep corrupting my excel files?

I'm trying to apply styles to cells in my excel files using the openpyxl library. If I try this (using an existing style and modifying it):
import openpyxl
wkbk = openpyxl.load_workbook('example.xlsx')
views_sheet = wkbk['Sheet']
cell_ = views_sheet.cell(row=4,column=3)
cell_.style = '20 % - Accent1'
bd = openpyxl.styles.Side(color=openpyxl.styles.colors.Color(theme=29))
cell_.border = openpyxl.styles.Border(left=bd, top=bd, right=bd, bottom=bd)
cell_.font = openpyxl.styles.Font(name='Calibri',size=11,bold=False,italic=False,vertAlign=None,underline='none',strike=False)
wkbk.save('example.xlsx')
I open 'example.xlsx' I get that my file is corrupted/needs to be restored. I thought that maybe it isn't possible writing over some existing style, so I created a new named style "highlight" with the associated color:
highlight = openpyxl.styles.NamedStyle(name="highlight")
highlight.fill = openpyxl.styles.PatternFill(bgColor=openpyxl.styles.colors.Color(theme=30),fill_type='shaded',patternType='lightGray')
bd = openpyxl.styles.Side(color=openpyxl.styles.colors.Color(theme=29))
highlight.border = openpyxl.styles.Border(left=bd, top=bd, right=bd, bottom=bd)
highlight.font = openpyxl.styles.Font(name='Calibri',size=11,bold=False,italic=False,vertAlign=None,underline='none',strike=False)
wkbk.add_named_style(highlight)
cell_.style = 'highlight'
But then I keep getting a ValueError indicating that I need to provide a value for parameter 'patternType' of class 'PatternFill'. This clearly does not makes sense.
Maybe I'm doing this wrong (it's hard to follow the documentation; had to look up older analogous implementations/snippets). Would appreciate some help.
Thank you!
I realize this is very late, but I had a similar issue where openpyxl was corrupting my .xlsx files when I tried to write a Pandas dataframe to an Excel workbook. The issue turned out to be that the workbook had some other tabs with formulas in certain cells, and for some reason the formulas get corrupted when openpyxl runs. I don't understand why, but the "fix" is to remove the formulas (so, hardcode anything you can).

Openpyxl Reading Non-empty Cells as None [duplicate]

I have a simple excel file:
A1 = 200
A2 = 300
A3 = =SUM(A1:A2)
this file works in excel and shows proper value for SUM, but while using openpyxl module for python I cannot get value in data_only=True mode
Python code from shell:
wb = openpyxl.load_workbook('writeFormula.xlsx', data_only = True)
sheet = wb.active
sheet['A3']
<Cell Sheet.A3> # python response
print(sheet['A3'].value)
None # python response
while:
wb2 = openpyxl.load_workbook('writeFormula.xlsx')
sheet2 = wb2.active
sheet2['A3'].value
'=SUM(A1:A2)' # python response
Any suggestions what am I doing wrong?
It depends upon the provenance of the file. data_only=True depends upon the value of the formula being cached by an application like Excel. If, however, the file was created by openpyxl or a similar library, then it's probable that the formula was never evaluated and, thus, no cached value is available and openpyxl will report None as the value.
I have replicated the issue with Openpyxl and Python.
I am currently using openpyxl version 2.6.3 and Python 3.7.4. Also I am assuming that you are trying to complete an exercise from ATBSWP by Al Sweigart.
I tried and tested Charlie Clark's answer, considering that Excel may indeed cache values. I opened the spreadsheet in Excel, copied and pasted the formula into the same exact cell, and finally saved the workbook. Upon reopening the workbook in Python with Openpyxl with the data_only=True option, and reading the value of this cell, I saw the proper value, 500, instead of the wrong value, the None type.
I hope this helps.
I had the same issue. This may not be the most elegant solution, but this is what worked for me:
import xlwings
from openpyxl import load_workbook
excel_app = xlwings.App(visible=False)
excel_book = excel_app.books.open('writeFormula.xlsx')
excel_book.save()
excel_book.close()
excel_app.quit()
workbook = load_workbook(filename='writeFormula.xlsx', data_only=True)
I have suggestion to this problem. Convert xlsx file to csv :).
You will still have the original xlsx file. The conversion is done by libreoffice (it is that subprocess.call() line).You can use also Pandas for this as a more pythonic way.
from subprocess import call
from openpyxl import load_workbook
from csv import reader
filename="test"
wb = load_workbook(filename+".xlsx")
spread_range = wb['Sheet1']
#what ever function there is in A1 cell to be evaluated
print(spread_range.cell(row=1,column=1).value)
wb.close()
#this line can be done with subprocess or os.system()
#libreoffice --headless --convert-to csv $filename --outdir $outdir
call("libreoffice --headless --convert-to csv "+filename+".xlsx", shell=True)
with open(filename+".csv", newline='') as f:
reader = reader(f)
data = list(reader)
print(data[0][0])
or
# importing pandas as pd
import pandas as pd
# read an excel file and convert
# into a dataframe object
df = pd.DataFrame(pd.read_excel("Test.xlsx"))
# show the dataframe
df
I hope this helps somebody :-)
Yes, #Beno is right. If you want to edit the file without touching it, you can make a little "robot" that edits your excel file.
WARNING: This is a recursive way to edit the excel file. These libraries are depend on your machine, make sure you set time.sleep properly before continuing the rest of the code.
For instance, I use time.sleep, subprocess.Popen, and pywinauto.keyboard.send_keys, just add random character to any cell that you set, then save it. Then the data_only=True is working perfectly.
for more info about pywinauto.keyboard: pywinauto.keyboard
# import these stuff
import subprocess
from pywinauto.keyboard import send_keys
import time
import pygetwindow as gw
import pywinauto
excel_path = r"C:\Program Files\Microsoft Office\root\Office16\EXCEL.EXE"
excel_file_path = r"D:\test.xlsx"
def focus_to_window(window_title=None): # function to focus to window. https://stackoverflow.com/a/65623513/8903813
window = gw.getWindowsWithTitle(window_title)[0]
if not window.isActive:
pywinauto.application.Application().connect(handle=window._hWnd).top_window().set_focus()
subprocess.Popen([excel_path, excel_file_path])
time.sleep(1.5) # wait excel to open. Depends on your machine, set it propoerly
focus_to_window("Excel") # focus to that opened file
send_keys('%{F3}') # excel's name box | ALT+F3
send_keys('AA1{ENTER}') # whatever cell do you want to insert somthing | Type 'AA1' then press Enter
send_keys('Stackoverflow.com') # put whatever you want | Type 'Stackoverflow.com'
send_keys('^s') # save | CTRL+S
send_keys('%{F4}') # exit | ALT+F4
print("Done")
Sorry for my bad english.
As others already mentioned, Openpyxl only reads cashed formula value in data_only mode. I have used PyWin32 to open and save each XLSX file before it's processed by Openpyxl to read the formulas result value. This works for me well, as I don't process large files. This solution will work only if you have MS Excel installed on your PC.
import os
import win32com.client
from openpyxl import load_workbook
# Opening and saving XLSX file, so results for each stored formula can be evaluated and cashed so OpenPyXL can read them.
excel_file = os.path.join(path, file)
excel = win32com.client.gencache.EnsureDispatch('Excel.Application')
excel.DisplayAlerts = False # disabling prompts to overwrite existing file
excel.Workbooks.Open(excel_file )
excel.ActiveWorkbook.SaveAs(excel_file, FileFormat=51, ConflictResolution=2)
excel.DisplayAlerts = True # enabling prompts
excel.ActiveWorkbook.Close()
wb = load_workbook(excel_file)
# read your formula values with openpyxl and do other stuff here
I ran into the same issue. After reading through this thread I managed to fix it by simply opening the excel file, making a change then saving the file again. What a weird issue.

Reading cell value without redefining it with Openpyxl

I need to read this .xlsm database and some of the cells values I need are derived from Excel functions. To accomplish this I used:
from openpyxl import load_workbook
wb = load_workbook('file.xlsm', data_only=True, keep_vba=True)
ws = wb['Plan1']
And then, for every cell I wanted to read:
ws.cell(row=row, column=column).value
This works fine for getting the data out. But the problem comes with saving. When I do:
wb.save('file.xlsm')
It saves the file, but all the formulas inside the sheets are lost
My dilemma is reading the cell's displayed values on one of the database's sheet without modifying them, writing the code's output in a new sheet and saving it.
Read the file once in read-only and data-only mode to look at the values and another time keeping the VBA around. And save under a different name.

Update .xlsm file values python

I have a .xlsm file as a reference template. I want to update the values of this .xlsm file using python from a .csv file.
template .xlsm ----> Update values using .csv
What has not worked :
I tried using pandas.to_excel method. but the .xlsm file gets corrupted after I write to sheet.
Could someone please point me in the right direction ?
openpyxl supports xlsm file.
from openpyxl import load_workbook
wb2 = load_workbook('test.xlsm', keep_vba=True)
update(wb2, csvfile.csv) # this is where you need to work according to your need.
wb.save('new_document.xlsm')
wb.close()
https://openpyxl.readthedocs.io/en/default/tutorial.html
Maybe to try xlwings, using it something like this?
def update(workbook, csv_file):
ws = workbook.sheets[2]
ws.range('B14').value = 155
from xlwings import Book
wb = Book(r'test.xlsm')
update(wb, csv_file)
wb.save('test1.xlsm')
wb.close()
This is the best tool to update xlsm files since it uses WindowsAPI and macros are triggered in case something is changed. This means, it won't work on Linux.
Of course, update function must do something more meaningful than changing the B14 cell in the 3rd sheet.
For more info, please read http://docs.xlwings.org/en/stable/quickstart.html

"Worksheet range names does not exist" KeyError in openpyxl

Let me preface this by saying I have tried looking for, and cannot seem to find a similar situation so please don't be too upset if this seems familiar to you. I am using Python 2.7 and openpyxl version 2.2.5 (I need to use 2.7, and used an older module for other reasons.)
I am new to Python and read/write code in general, so I'm testing this on the command line before I implement it:
I created a file, foo.xlsx in the Python27 file directory with some values that I manually entered via Excel.
I then used this simple code on the Python command line to test my code
from openpyxl import load_workbook
wb = load_workbook('foo.xlsx')
sheet_ranges = wb['range names']
It then resulted in the following error:
File "C:\Python27\lib\openpyxl\workbook.workbook.py", line 233 in getitem
raise KeyError("Worksheet {0} does not exist.".format(key))
KeyError: 'Worksheet sheet range names does not exist'
So I thought it had something to do with not importing the entire openpyxl module. I proceeded to do that and run the whole process but it resulted in the same error.
Can someone please let me know what I am doing wrong/how to solve this?
Additional information:
I had successfully written to an empty file before, and then read the values. This gave me the right values for everything EXCEPT what I had written in manually via Excel- the cells that had manual input returned None or Nonetype. The issue seems to be with cells with manual input.
I did hit save on the file before accessing it don't worry
This was in the same directory so I know that it wasn't a matter of location.
The following command does not make sense:
sheet_ranges = wb['range names']
Normally you open a workbook and then access one of the worksheets, the following gives you some examples on how this can be done:
import openpyxl
wb = openpyxl.Workbook()
wb = openpyxl.load_workbook(filename = 'input.xlsx')
# To display all of the available worksheet names
sheets = wb.sheetnames
print sheets
# To work with the first sheet (by name)
ws = wb[sheets[0]]
print ws['A1'].value
# To work with the active sheet
ws = wb.active
print ws['A1'].value
# To work with the active sheet (alternative method)
ws = wb.get_active_sheet()
print ws['A1'].value
If you want to display any named range in the workbook, you can do the following:
print wb.get_named_ranges()
I'm not exactly sure what it is you need to do, but to read Excel spreadsheets into python, I usually use xlrd (which to me was easier to get use to). See example:
import xlrd
workbook = xlrd.open_workbook(in_fname)
worksheet = workbook.sheet_by_index(0)
To write to Excel spreadsheets, I use xlsxwriter:
import xlsxwriter
workbook = xlsxwriter.Workbook(out_fname)
worksheet = workbook.add_worksheet('spreadsheet_name')
Hope this helps.

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