group by operation？ about alenka HOT 3 CLOSED

I use a combination of merge/reduce_by_key operations.
You can look at merge.cu file to see how it is done.

Regards, Anton

from alenka.

the early version of merge every segment of groupby result using unordermap seems can not make sure the merge result in groupby order by gropuby multiple keys , and is the new version can make sure that the result is in order instead of put the new record just after the old record?

from alenka.

This is what it does, puts the records with equal keys one after another using thrust::merge. In the end it uses reduce_by_key to combine the neighbor records with equal keys into one record.

from alenka.