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Aggregate strings on a groupby operation

See original GitHub issue

Hi.

I need to group a dataframe and aggregate the strings as a list or a set. I have many string columns in the dataframe. How can I do that in vaex? This is the functionality I’m looking for:

d
   A       B
0  1    This
1  2      is
2  3       a
3  4  random
4  1  string
5  2       !

 d.groupby('A')['B'].apply(list)
A
1    [This, string]
2           [is, !]
3               [a]
4          [random]
dtype: object

Thanks!

Issue Analytics

State:
Created 3 years ago
Reactions:2
Comments:18 (8 by maintainers)

Top GitHub Comments

2reactions

kylegildecommented, Sep 15, 2021

Is this use case supported at this point? I don’t really see how to use AggregatorDescriptorMulti to do this task.

1reaction

JovanVeljanoskicommented, Nov 18, 2022

I understand but first step is creating the “dict” object right? Then the aggregation begins. Unless you already have data in that form (via pyarrow structs).

But please create a new issue on this, since it is going away from the original topic of this thread.

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