How to avoid Python/Pandas creating an index in a saved csv?

534
votes

I am trying to save a csv to a folder after making some edits to the file.

Every time I use pd.to_csv('C:/Path of file.csv') the csv file has a separate column of indexes. I want to avoid printing the index to csv.

I tried: 

pd.read_csv('C:/Path to file to edit.csv', index_col = False)

And to save the file...

pd.to_csv('C:/Path to save edited file.csv', index_col = False)

However, I still got the unwanted index column. How can I avoid this when I save my files?

6
pythoncsvindexingpandas
try index=False instead of index_col – Jeff
Can we use this in ms excel as well? – Nabih Ibrahim Bawazir
Yes you can pd.to_excel(r'file.xlsx', index = False) – bfree67
index_col works for read_html() as well. – caram

6 Answers

809
votes

Use index=False.

df.to_csv('your.csv', index=False)
115
votes

There are two ways to handle the situation where we do not want the index to be stored in csv file.

  1. As others have stated you can use index=False while saving your
    dataframe to csv file.

    df.to_csv('file_name.csv',index=False)

  2. Or you can save your dataframe as it is with an index, and while reading you just drop the column unnamed 0 containing your previous index.Simple!

    df.to_csv(' file_name.csv ')
    df_new = pd.read_csv('file_name.csv').drop(['unnamed 0'],axis=1)

82
votes

If you want no index, read file using:

import pandas as pd
df = pd.read_csv('file.csv', index_col=0)

save it using 

df.to_csv('file.csv', index=False)
27
votes

As others have stated, if you don't want to save the index column in the first place, you can use df.to_csv('processed.csv', index=False)

However, since the data you will usually use, have some sort of index themselves, let's say a 'timestamp' column, I would keep the index and load the data using it.

So, to save the indexed data, first set their index and then save the DataFrame:

df.set_index('timestamp')
df.to_csv('processed.csv')

Afterwards, you can either read the data with the index:

pd.read_csv('processed.csv', index_col='timestamp')

or read the data, and then set the index:

pd.read_csv('filename.csv')
pd.set_index('column_name')
17
votes

Another solution if you want to keep this column as index. 

pd.read_csv('filename.csv', index_col='Unnamed: 0')
9
votes

If you want a good format the next statement is the best:

dataframe_prediction.to_csv('filename.csv', sep=',', encoding='utf-8', index=False)

In this case you have got a csv file with ',' as separate between columns and utf-8 format. In addition, numerical index won't appear.