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Add column to CSV using Pandas - nsadams87xx - Apr-06-2020
Hey everyone,
I have a list that I made as a dataframe and I want to take this dataframe and add it to an existing CSV file with data already in it.
The csv has three columns already,
Date,Confirmed,Deaths
2/29/2020,2,0
3/1/2020,3,0
3/2/2020,4,0
3/3/2020,4,0
3/4/2020,4,0
3/5/2020,5,0
3/6/2020,5,0
3/7/2020,6,0
3/8/2020,7,0
3/9/2020,7,0
...
My column I want to add is "New Cases". Yes, you can guess what this is about.....
I used this code and figured out quickly that this overwrites the whole CSV:
df = pd.DataFrame(data={"New_Cases": case_list})
df.to_csv("./Cook County.csv", sep=',',index=False)
RE: Add column to CSV using Pandas - UGuntupalli - Apr-15-2020
@nsadams87xx,
First suggestion is to follow Larz60+ advice and reformat your question. As for your original problem, a very easy way to fix that would be:
- Use Pandas to read the original csv into a dataframe
- Concatenate your original dataframe to the dataframe you created from the csv
- Write the new dataframe to a csv
RE: Add column to CSV using Pandas - snippsat - Apr-15-2020
As mention bye @UGuntupall so is the first step to get the .csv read into a DataFrame.
Then should a search help as adding a new column to a DataFram is very basic task in Pandas.
Here Notebook you can look at.