I read an Excel Sheet this way :
import pandas as pd
xl = pd.ExcelFile("Path\file_name.xlsx")
xl.parse("Sheet_name")
and now I make some changes, for example I fill all null values with string "NA"
df = df.fillna("NA")
now I wish to write back the changes to the original Excel file...
You could simply write the changed data to the existing file using to_excel:
df.to_excel("Path\file_name.xlsx", "Sheet_name")
I would work with CSV files if you have large data sets.
save excel as .csv
data = pd.read_csv('name.csv')
data.to_csv('name.csv')
Related
I have an excel file that contains the names of 60 datasets.
I'm trying to write a piece of code that "enters" the Excel file, accesses a specific dataset (whose name is in the Excel file), gathers and analyses some data and finally, creates a new column in the Excel file and inserts the information gathered beforehand.
I can do most of it, except for the part of adding a new column and entering the data.
I was trying to do something like this:
path_data = **the path to the excel file**
recap = pd.read_excel(os.path.join(path_data,'My_Excel.xlsx')) # where I access the Excel file
recap['New information Column'] = Some Value
Is this a correct way of doing this? And if so, can someone suggest a better way (that works ehehe)
Thank you a lot!
You can import the excel file into python using pandas.
import pandas as pd
df = pd.read_excel (r'Path\Filename.xlsx')
print (df)
If you have many sheets, then you could do this:
import pandas as pd
df = pd.read_excel (r'Path\Filename.xlsx', sheet_name='sheetname')
print (df)
To add a new column you could do the following:
df['name of the new column'] = 'things to add'
Then when you're ready, you can export it as xlsx:
import openpyxl
# to excel
df.to_excel(r'Path\filename.xlsx')
So I want to have 1 script writing continually to a CSV file, and another script reading periodically from that same CSV file.
What I'm looking for is a way to delete the rows I've just read in from the CSV file (not from my pandas dataframe).
Can anybody help?
# Read data in to dataframe
deviceInfo = pd.read_csv("sampleData.csv", nrows = 100)
# Somehow delete those 100 rows from the CSV file
#JoseAngelSanchez is correct that you might want to read the whole csv into a dataframe, but I think this way lets you get a dataframe with the first 100 rows and still delete them from the csv file.
import pandas as pd
df = pd.read_csv("sampleData.csv")
deviceInfo = df.iloc[:100]
df.iloc[100:].to_csv("sampleData.csv")
Note: if you're doing this repetitively then you'll probably want to write to_csv(...,index=None) or a new index column will be created in the .csv file on each iteration.
You should read the whole document and then delete the rows you don't want
import pandas as pd
df = pd.read_csv("sampleData.csv")
df = df.iloc[100:]
df.to_csv("sampleData.csv")
I have a text file that contains data like this. It is is just a small example, but the real one is pretty similar.
I am wondering how to display such data in an "Excel Table" like this using Python?
The pandas library is wonderful for reading csv files (which is the file content in the image you linked). You can read in a csv or a txt file using the pandas library and output this to excel in 3 simple lines.
import pandas as pd
df = pd.read_csv('input.csv') # if your file is comma separated
or if your file is tab delimited '\t':
df = pd.read_csv('input.csv', sep='\t')
To save to excel file add the following:
df.to_excel('output.xlsx', 'Sheet1')
complete code:
import pandas as pd
df = pd.read_csv('input.csv') # can replace with df = pd.read_table('input.txt') for '\t'
df.to_excel('output.xlsx', 'Sheet1')
This will explicitly keep the index, so if your input file was:
A,B,C
1,2,3
4,5,6
7,8,9
Your output excel would look like this:
You can see your data has been shifted one column and your index axis has been kept. If you do not want this index column (because you have not assigned your df an index so it has the arbitrary one provided by pandas):
df.to_excel('output.xlsx', 'Sheet1', index=False)
Your output will look like:
Here you can see the index has been dropped from the excel file.
You do not need python! Just rename your text file to CSV and voila, you get your desired output :)
If you want to rename using python then -
You can use os.rename function
os.rename(src, dst)
Where src is the source file and dst is the destination file
XLWT
I use the XLWT library. It produces native Excel files, which is much better than simply importing text files as CSV files. It is a bit of work, but provides most key Excel features, including setting column widths, cell colors, cell formatting, etc.
saving this is:
df.to_excel("testfile.xlsx")
I have an excel sheet and I am reading the excel sheet using pandas in python.
Now I want to read the excel file based on a column, if the column has some value then do not read that row, if the column is empty than read that and store the values in a list.
Here is a screenshot
Excel Example
Now in the above image when the uniqueidentifier is yes then it should not read that value, but if it is empty then it should start reading from that value.
How to do that using python and how to get index so that after I have performed some function that I am again able to write to that blank unique identifier column saying that row has been read
This is possible for csv files. There you could do
iter_csv = pandas.read_csv('file.csv', iterator=True, chunksize=100000)
df = pd.concat([chunk[chunk['UniqueIdentifier'] == 'True'] for chunk in iter_csv])
But pd.read_excel does not offer to return an iterator object, maybe some other excel-readers can. But I don't no which ones. Nevertheless you could export your excel file as csv and use the solution for csv files.
How to get data from one Excel sheet and write on another Excel Sheet using Python?
Eg:
I have Excel name Original Sheet with come contents i need to read those contents and write on another Excel name Copy Sheet By Using Python.
Note : Read and Write both should be done by using Python Code
You can use the pandas library to do this
import pandas as pd
df = pd.read_excel('original_sheet.xlsx')
df.to_excel('copy_sheet.xlsx')