Supporting multiple taxons with tax2filter

[zhan4429]

Description of feature

The current version of tax2filter only allows the filtering out of a single taxon. However, it would be more useful if it could support multiple taxons separated by either a comma or semicolon. In my metagenomics project, I need to filter out human, bacteria, and archaea. Unfortunately, the current version of detaxizer does not permit filtering out all three taxons in one pipeline run.