classify document to topic

[lksv]

At first, thanks for this gem.

By this gem I can create a topics (categories). That is perfect! Is there a way how to classify document by the created topic? What would you suggest?

[ealdent]

Sure, the method #compute_topic_document_probability in the Lda class returns a matrix of documents x topics with the average log probability. I'd start there and then build a classifier, which may just be setting a threshold value that you tweak until you get acceptable results.