Hallo!
adaptive is a PD-external library for adaptive systems and filters.
We (Gerda Stroble + me) implemented various versions of the LMS (least mean square) and NLMS algorithm and also added a lot of examples (see PD-patches in example folder): system identification, interference cancelation, adaptive equalization, decision-directed equalization, ...
A RLS (recursive least square) algorithm and more example patches (e.g. echo cancelation, ...) will follow when I have to learn for the exam ... :)
For more documentation and tarballs look here: http://grh.mur.at/software/adaptive.html
LG Georg