openpyxl python - writing csv to excel gives 'number formatted as text'

Question

I have written a code to import a .csv file (containing numbers) into an excel file through openpyxl. It works, however, all the cells have written the numbers to the excel file as text. I then have to manually correct the error in excel: "Numbers formatted as text (displaying little green triangles in the corner of the cell).

Is there a way to prevent this from happening? It occurs with any csv file, even if I make it with just numbers. Thanks

#!python2
# Add csv file to an xlsx

import os, csv, sys, openpyxl
from openpyxl import load_workbook
from openpyxl import Workbook
from openpyxl.cell import get_column_letter


#Open an xlsx for reading
wb = load_workbook('Test.xlsx')
ws = wb.get_sheet_by_name("RUN")

dest_filename = "Test_NEW.xlsx"
csv_filename = "csvfile.csv"

#Copy in csv
f = open(csv_filename)
reader = csv.reader(f)
for row_index, row in enumerate(reader):
    for column_index, cell in enumerate(row):
        column_letter = get_column_letter((column_index + 1))
        ws.cell('%s%s'%(column_letter, (row_index + 1))).value = cell


wb.save(filename = dest_filename)

print "new Cashflow created"

*****UPDATE***

Thanks, that helps. My problem was that my csv file had a mixture of text and numbers without any defining quotes. So I implemented the below to change it from a string to float as long as there isn't an error.

#Copy in csv
f = open(csv_filename,'rb')
reader = csv.reader(f)
for row_index, row in enumerate(reader):
for column_index, cell in enumerate(row):
    column_letter = get_column_letter((column_index + 1))
    s = cell
    try:
        s=float(s)
    except ValueError:
        pass

    ws.cell('%s%s'%(column_letter, (row_index + 1))).value = s

Answer 1

You need to convert the value from the CSV file to what you need. All values in CSV files are strings. ws.cell('%s%s'%(column_letter, (row_index + 1))).value = int(cell) ought to do it.

BTW. you might want to look at the ws.append() method.

Answer 2

This is the first google result, and I spent more time than I would like to admit working on this. I hope it helps someone in the future.

def csvtoxlsx(csv_name, xlsx_name, directory, floats):
    """
    A function to convert a CSV file to XLSX so it can be used by openpyxl.
    csvname = file name of csv you want to convert (include .csv)
    xlsx_name = name you want to name the xlsx file (include .xlsx)
    cwd = directory to find csv file (can pass os.getcwd())
    floats = A list of column indexes in which floats appear
    """

    os.chdir(directory)

    f = open(csv_name, 'rt')
    csv.register_dialect('commas', delimiter=',')
    reader = csv.reader(f, dialect='commas')
    wb = Workbook()
    dest_filename = xlsx_name
    ws = wb.worksheets[0]
    ws.title = xlsx_name[:-5]

    for row_index, row in enumerate(reader):
        for column_index, cell in enumerate(row):

            column_letter = get_column_letter((column_index + 1))

            if column_index in floats:
                s = cell
                #Handles heading row or non floats
                try:
                    s = float(s)
                    ws[('%s%s'%(column_letter, (row_index + 1)))].value = s

                except ValueError:
                    ws[('%s%s'%(column_letter, (row_index + 1)))].value = s

            elif column_index not in floats:
                #Handles openpyxl 'illigal chars'
                try:
                    ws[('%s%s'%(column_letter, (row_index + 1)))].value = cell

                except:
                    ws[('%s%s'%(column_letter, (row_index + 1)))].value = 'illigal char'



    wb.save(filename = dest_filename)