Complexity

N - number of protein molecules in database.
O(n) - number of ``features'' in each protein structure.
R - number of reference frames, typically R=n,n<sup>2</sup>,n<sup>3</sup>
s - size of hash-table entry. s can be kept low by not processing ``fat'' entries.

Preprocessing:

O(N*R*n)

Recognition:

O(R*n*s)