Add Groupby Percentage to Dataframe after Calculation

Question

I have a DataFrame that looks like this:

I need to calculate the percentage based on the count column which I already did following this answer.

The result is this:

Now I need to add the results for the Groupby column back into the original DataFrame. I tried grouped.reset_index() and then adding it but I get an error ValueError: cannot insert count, already exists since the column used in the Group by is also used in the aggregation.

Can anyone help me to find a way to add the results back to the DataFrame?

You want the whole result to be added or only the count column? — bigbounty, May 08 '17 at 05:59
Get into the habit of posting data and not images. There are many reasons to hate images. My reason is that I can't copy/paste it into my environment and produce more descriptive answers. — piRSquared, May 08 '17 at 06:07
Feel free to up vote the answer as well. I'd appreciate it thx. — piRSquared, May 08 '17 at 06:38

score 1 · Accepted Answer · answered May 08 '17 at 06:05

1

You want to use transform and that answer you linked could be better as well.

df.assign(
    NormalizedCount=df['count'] / df.groupby('suburb')['count'].transform('sum')

answered May 08 '17 at 06:05

piRSquared

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Add Groupby Percentage to Dataframe after Calculation

1 Answers1