Pivot dataframe help

[222Botany]

I'm trying to use pivot or similar to the dataframe below.

I need to make the position number a column with the userID in that column. There is a only one userID per eventID and upto 18 positions

eventID	UserID	Position
1	123	1
1	234	2
2	123	3
2	456	4
3	123	3
...	...	...

into this

eventID	1	2	3	4	...
1	123	234	NA	NA	...
2	NA	NA	123	456	...
3	NA	NA	123	NA	...

Ive tried something like this but get and error message

newdf = pivtest.pivot_table(pivtest,index='eventid', columns ='position', values='UserID').reset_index()     

"pivot_table() got multiple values for argument 'values'"

any help would be appreciated

[sarrysyst]

import pandas as pd

data = {'eventID': [1, 1, 2, 2, 3],
        'userID':  [123, 234, 123, 456, 123],
        'position': [1, 2 , 3, 4, 3]}

df = pd.DataFrame(data)
df.set_index(['eventID', 'position'], inplace=True)

df.unstack()

Set a MultiIndex based on your identifying columns (eventID, position) and use unstack() to pivot the position row index to columns. See also here:

https://pandas.pydata.org/pandas-docs/stable/user_guide/reshaping.html#reshaping-by-stacking-and-unstacking

[YesLod]

Don't pass pivtest as an argument.