In case someone comes to this thread from Google looking to assign torrents to categories based on tracker URLs, here's how I did it. I wanted Tixati to automatically assign category "Private" for any torrents downloaded from private trackers, and "Public" for torrents downloaded from anywhere else (public trackers).
For Private category my setup is like this:
Transfer Load
Match:
.*(http|https):\/\/tracker\.(privatesite1|privatesite2)\.(com|net).*
(Regex selected from dropdown)
Exclude: leave blank
And for Public category, we want to match everything, excluding the private ones:
Transfer Load
Match:
.
(Regex selected from dropdown)
Exclude:
.*(http|https):\/\/tracker\.(privatesite1|privatesite2)\.(com|net).*
(Regex selected from dropdown)
If someone has a better understanding of these capture settings and some spare time, this help document could use some work:
https://support.tixati.com/categories .