symmetry

3D symmetry search algorithm

This may be more appropriate for math overflow, but nevertheless: Given a 3D structure (for example, a molecule), what is a good approach/algorithm to find symmetry (rotational/reflection/inversion/etc.)? I came up with brute force naïve algorithm, but it seems there should be better approach. I am not so much interested in genetic alg...

Overriding equals method without breaking symmetry in a class that has a primary key

Hi, the answer to this question is probably "not possible", but let me ask regardless :) Assuming we have a very simple JAVA class that has a primary key, for example: class Person { String ssid; String name; String address; ... } Now, I want to store people in a collection, meaning I will have to override the equals...

Computer algebra for Clojure

Short version: I am interested in some Clojure code which will allow me to specify the transformations of x (e.g. permutations, rotations) under which the value of a function f(x) is invariant, so that I can efficiently generate a sequence of x's that satisfy r = f(x). Is there some development in computer algebra for Clojure? For (a tri...