Your link is broken so I dont know what you want. I depends what you are looking for, but Ill bet the answer coul dbe found in either one of the articles here on codeproject, or in the bok "The NURBS book" as it contains several curve fitting algorithms.
Edit:
Or you could search for "curve fit" on this page:
http://www.netlib.org/cgi-bin/search.pl[
^]
The algorithms on this page is considered so imporatant that the reasearch community decided to give out the program code, however it might be licenced and only free for research.