   uml class diagram for graph like system
  I am trying to figure out what a UML class diagram would look like for a system designed like a graph data structure. The system is a series of relationships (R# is the relationship, A,B,C are the nodes):R1 = A----BR2 = B----CR3 = A---B----CIn my case the relationships are the most important part. R1 can actually represent the relationship between a lot of nodes. But there is only one type of relationship R1. I am trying to come up with a UML diagram for such a system, and was wondering if anyone can give some advice to point me in the right direction.   
  I'm afraid your explanation is quite obscure, as you only mention two types (relationships and nodes), one of which you explain nothing about (nodes). What would be the trouble with a setup as follows:class 'a relationship = sig  arity : int;  related : 'a vect -> bool;end;;'a represents the node type you intend to use, and related determines if an array of nodes satisfy the relationship by returning true or false. 