GroupBy Node converts my DataType to DoubleValue

Node Development
1

Hello,

I created a new DataType which is called AttributeValue. The class Attribute extends DataCell and implements AttributeValue, DoubleValue, BoundedValue. It has also some additional data besides the value, which I need for my visualization node.
It works great, but there is a problem with the GroupBy Node. When I use it with the “Mean” aggregation method it throws away my AttributeCell (with all the additional data) and creates a new DoubleCell.
Is there a possiblity to avoid the creation of the DoubleCell? Why doesn’t the GroupBy node use my AttributeValue for calculating the mean value?

Thanks for any response :slight_smile:

2

The simple reason for this is that the GroupBy node needs to create a new cell, which it can only do with base types (such as DoubleCell). It doesn’t know how to create your cell instance. That’s different from, for instance calculating the minimum or maximum, where can actually use an instance from the input data.

Does that answer your question?

3