Graph structured program evolution with automatically defined nodes

Currently, various automatic programming techniques have been proposed and applied in various fields. Graph Structured Program Evolution (GRAPE) is a recent automatic programming technique with graph structure. This technique can generate complex programs automatically. In this paper, we introduce the concept of automatically defined functions, called automatically defined nodes (ADN), in GRAPE. The proposed GRAPE program has a main program and several subprograms. We verified the effectiveness of ADN through several program evolution experiments, and report the results of evolution of recursive programs using GRAPE modified with ADN.