Generate Aggregation and Group by

aruberutou

Hello,

I would like to count each unique item in a column, and create a new column with the corresponding count information for each item.

In excel, I would simply use =countif(ColumnA, ColumnA(i)) and copy down.

I expected that to be equally simple in RapidMiner; perhaps using GenerateAttribute. However, this is no "group by" function, and so my count column always returns "1" for each value.

Am I overlooking something?

aruberutou

Okay,

I feel silly. Its seems a simple solution was to multiply the data, aggregate one thread, then rejoin using the aggregated attribute as the key.

Its still messier than I would have hoped, but perfectly usable, I guess.

Nevertheless, please let me know if I am missing something.