keeping the same file format when saving .xlsx file using python - python

Im working on a project where I have to take excel file make changes to the data and save it
from pandas import ExcelWriter
import pandas as pd
dfs = pd.read_excel("infile.xlsx")
#manuplate data
writer = ExcelWriter('outfile.xlsx')
dfs.to_excel(writer,'Sheet5')
writer.save()
The problem I have is the newly saved excel file does not have the same format(cell widht, bold borders) as the input file. What can I do to solve this issue?

You can't preserve the formatting because pandas throws away all that information upon import. You would need to specify the formatting options you want in the output with the ExcelWriter object. If you use the option engine='xlsxwriter' you can then use all the xlsxwriter formatting options before writing the final file. You can find more details in the XlsxWriter documentation.
Example:
import pandas as pd
# This removes the default header style so we can override it later
import pandas.io.formats.excel
pandas.io.formats.excel.header_style = None
# Create a Pandas dataframe from some data.
df = pd.DataFrame({'Data1': [10, 20, 30, 20, 15, 30, 45],
'Data2': [90, 80, 30, 15, 88, 34, 41]})
# Create a Pandas Excel writer using XlsxWriter as the engine.
writer = pd.ExcelWriter('pandas_conditional.xlsx', engine='xlsxwriter')
# Convert the dataframe to an XlsxWriter Excel object.
df.to_excel(writer, sheet_name='Sheet1')
# Get the xlsxwriter workbook and worksheet objects.
workbook = writer.book
worksheet = writer.sheets['Sheet1']
# Create Format objects to apply to sheet
# https://xlsxwriter.readthedocs.io/format.html#format-methods-and-format-properties
red_bold = workbook.add_format({'bold': True, 'font_color': 'red'})
border = workbook.add_format({'border':5, 'border_color':'blue'})
#Apply formatting to sheet
worksheet.set_column('C:C', None, red_bold)
worksheet.set_column('A1:A8', None, border)
# Apply a conditional format to a cell range.
worksheet.conditional_format('B2:B8', {'type': '3_color_scale'})
# Close the Pandas Excel writer and output the Excel file.
writer.save()

Related

How to add Pandas dataframe to an existing xlsx file using to_excel

I have write some content to a xlsx file by using xlsxwriter
workbook = xlsxwriter.Workbook(file_name)
worksheet = workbook.add_worksheet()
worksheet.write(row, col, value)
worksheet.close()
I'd like to add a dataframe after the existing rows to this file by to_excel
df.to_excel(file_name,
startrow=len(existing_content),
engine='xlsxwriter')
However, this seems not work.The dataframe not inserted to the file. Anyone knows why?
Unfortunately, as the content above is not specifically written, let's take a look at to_excel and XlsxWriter as examples.
using xlsxwriter
import xlsxwriter
# Create a new Excel file and add a worksheet
workbook = xlsxwriter.Workbook('example.xlsx')
worksheet = workbook.add_worksheet()
# Add some data to the worksheet
worksheet.write('A1', 'Language')
worksheet.write('B1', 'Score')
worksheet.write('A2', 'Python')
worksheet.write('B2', 100)
worksheet.write('A3', 'Java')
worksheet.write('B3', 98)
worksheet.write('A4', 'Ruby')
worksheet.write('B4', 88)
# Save the file
workbook.close()
Using the above code, we have saved the table similar to the one below to an Excel file.
Language
Score
Python
100
Java
98
Ruby
88
Next, if we want to add rows using a dataframe.to_excel :
using to_excel
import pandas as pd
# Load an existing Excel file
existing_file = pd.read_excel('example.xlsx')
# Create a new DataFrame to append
df = pd.DataFrame({
'Language': ['C++', 'Javascript', 'C#'],
'Score': [78, 97, 67]
})
# Append the new DataFrame to the existing file
result = pd.concat([existing_file, df])
# Write the combined DataFrame to the existing file
result.to_excel('example.xlsx', index=False)
The reason for using pandas concat:
To append, it is necessary to use pandas.DataFrame.ExcelWriter(), but XlsxWriter does not support append mode in ExcelWriter
Although the task can be accomplished using pandas.DataFrame.append(), the append method is slated to be deleted in the future, so we use concat instead.
The OP is using xlsxwriter in the engine parameter. Per XlsxWriter documentation "XlsxWriter is designed only as a file writer. It cannot read or modify an existing Excel file." (link to XlsxWriter Docs).
Below I've provided a fully reproducible example of how you can go about modifying an existing .xlsx workbook using the openpyxl module (link to Openpyxl Docs).
For demonstration purposes, I'll first create create a workbook called test.xlsx using pandas:
import pandas as pd
df = pd.DataFrame({'Col_A': [1,2,3,4],
'Col_B': [5,6,7,8],
'Col_C': [0,0,0,0],
'Col_D': [13,14,15,16]})
df.to_excel('test.xlsx', index=False)
This is the Expected output at this point:
Using openpyxl you can use another dataset to load the existing workbook ('test.xlsx') and modify the third column with different data from the new dataframe while preserving the other existing data. In this example, for simplicity, I update it with a one column dataframe but you could extend it to update or add more data.
from openpyxl import load_workbook
import pandas as pd
df_new = pd.DataFrame({'Col_C': [9, 10, 11, 12]})
wb = load_workbook('test.xlsx')
ws = wb['Sheet1']
for index, row in df_new.iterrows():
cell = 'C%d' % (index + 2)
ws[cell] = row[0]
wb.save('test.xlsx')
With the Expected output at the end:

How to write a Dataframe and images to separate worksheets of an excel file

I have found a similar and well answered question, Python: Writing Images and dataframes to the same excel file, but the answer writes the image into the same sheet as the Dataframe. I have 5 images I want to write to separate worksheet to that of the Dataframe.
As this answer is well written I shall use it here if that is ok and ask how to write any 2 images to a separate worksheet in the created workbook?
Code
import pandas as pd
# Create a Pandas dataframe from some data.
df = pd.DataFrame({'Data': [10, 20, 30, 20, 15, 30, 45]})
# Create a Pandas Excel writer using XlsxWriter as the engine.
writer = pd.ExcelWriter('pandas_image2.xlsx', engine='xlsxwriter')
# Convert the dataframe to an XlsxWriter Excel object.
df.to_excel(writer, sheet_name='Sheet1')
# Get the xlsxwriter workbook and worksheet objects.
workbook = writer.book
worksheet = writer.sheets['Sheet2']
# Insert an image.
worksheet.insert_image('D3', 'TRAJ_FIG.PNG')
# Close the Pandas Excel writer and output the Excel file.
writer.save()
Desired result
An excel workbook with two sheets, the df written to one and 2 images written to the other worksheet.
Instead of using writer, add a new sheet using workbook.add_worksheet():
with pd.ExcelWriter('pandas_image2.xlsx', engine='xlsxwriter') as writer:
df.to_excel(writer, sheet_name='Sheet1')
workbook = writer.book
worksheet = workbook.add_worksheet('Sheet2')
worksheet.insert_image('D3', 'TRAJ_FIG.PNG')

Append images to excel file

I have a requirement where i want to append images to my excel sheet.
code to add 1 image:
import pandas as pd
## Create a Pandas dataframe from some data.
df = pd.DataFrame({'Data': [10, 20, 30, 20, 15, 30, 45]})
##Create a Pandas Excel writer using XlsxWriter as the engine.
writer = pd.ExcelWriter('pandas_image.xlsx', engine='xlsxwriter')
## Convert the dataframe to an XlsxWriter Excel object.
df.to_excel(writer, sheet_name='Sheet1')
## Get the xlsxwriter workbook and worksheet objects.
workbook = writer.book
worksheet = writer.sheets['Sheet1']
## Insert an image.
worksheet.insert_image('D3', 'newImage.jpg')
## Close the Pandas Excel writer and output the Excel file.
writer.save()
#When I add 1 image to excel
**My requirement :**when I add new photos, it should get appended to my current data.
It should look like

How to copy and paste text file into a specified Excel TAB using Python?

I have 5 excel tabs in a certain sheet that I need to copy and paste text files into. I know how to a certain cell of a normal excel sheet with one tab. But I have no idea how to copy and paste each text file to the correct tab as there are formulas in each one.
Any ideas?
you can achive using python panda
import pandas as pd
# Create some Pandas dataframes from some data.
df1 = pd.DataFrame({'Data': [11, 12, 13, 14]})
df2 = pd.DataFrame({'Data': [21, 22, 23, 24]})
df3 = pd.DataFrame({'Data': [31, 32, 33, 34]})
# Create a Pandas Excel writer using XlsxWriter as the engine.
writer = pd.ExcelWriter('pandas_multiple.xlsx', engine='xlsxwriter')
# Write each dataframe to a different worksheet.
df1.to_excel(writer, sheet_name='Sheet1')
df2.to_excel(writer, sheet_name='Sheet2')
df3.to_excel(writer, sheet_name='Sheet3')
# Close the Pandas Excel writer and output the Excel file.
writer.save()

Problem with different indexing in pandas and xlsxwriter

Here is the code which works fine:
import pandas as pd
# Create a Pandas dataframe from some data.
df = pd.DataFrame({'Data': [10, 20, 30, 20, 15, 30, 45]})
# Create a Pandas Excel writer using XlsxWriter as the engine.
writer = pd.ExcelWriter('pandas_conditional.xlsx', engine='xlsxwriter')
# Convert the dataframe to an XlsxWriter Excel object.
df.to_excel(writer, sheet_name='Sheet1')
# Get the xlsxwriter workbook and worksheet objects.
workbook = writer.book
worksheet = writer.sheets['Sheet1']
# Apply a conditional format to the cell range.
worksheet.conditional_format(1,1,1,1, {'type': '3_color_scale'}) ##CHANGES THE COLOR OF SECOND ROW
# Close the Pandas Excel writer and output the Excel file.
writer.save()
This creates below output.
My question is, Is it possible to include the Header Data in the pandas indexing? I want to start indexing from 1st row. So Header Data should have index 0. It is useful because in xlsxwriter 1st row has index 0.
Firstly index is an object and default index starts from 0. You can swift it by typing:
df.index += 1
As for the header's index name pandas method to_excel takes an argument which is called index_label. So your code should be:
import pandas as pd
# Create a Pandas dataframe from some data.
df = pd.DataFrame({'Data': [10, 20, 30, 20, 15, 30, 45]})
df.index += 1
# Create a Pandas Excel writer using XlsxWriter as the engine.
writer = pd.ExcelWriter('pandas_conditional.xlsx', engine='xlsxwriter')
# Convert the dataframe to an XlsxWriter Excel object.
df.to_excel(writer, sheet_name='Sheet1', index_label='0')
# Get the xlsxwriter workbook and worksheet objects.
workbook = writer.book
worksheet = writer.sheets['Sheet1']
# Apply a conditional format to the cell range.
worksheet.conditional_format(1,1,1,1, {'type': '3_color_scale'}) ##CHANGES THE COLOR OF SECOND ROW
# Close the Pandas Excel writer and output the Excel file.
writer.save()
Output:

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