DATA GRAPHS AND ADDRESSING SCHEMES,

A data graph is obtained from a data structure by masking out the specific data items at the nodes of the structure and concentrating only on the linkages in the structure. This factoring operation is done implicitly when one refers to tree structures or arrays as generic objects. Structural uniformities in data graphs can often be exploited to facilitate and systematize the accessing of nodes in the graph and the implementation of the graph in a computer. The paper presents a model for data graphs which can be used to study such uniformities. The work reported herein represents the initial phase of an investigation of this model the emphasis is on obtaining precise formulations of relevant uniformities and investigating their mathematical consequences. In particular, the notions of implementation by relative addressing and relocatable implementation are introduced, and the classes of data graphs which can be so implemented are characterized. Author