Block diagram generation and parsing based on graph grammar

A block diagram is a graphical model with which it is possible to concisely visualize a system structure and is widely used in control engineering and other fields. However, there are few studies that try to formulate a syntax of block diagrams. In this research, we define a block diagram grammar which generates block diagrams by means of subgraph rewriting of a graph grammar. It includes some context-sensitive productions and is very concise. We have also developed a parser based on this block diagram grammar that parses a diagram in a bottom-up parallel method. It decides whether a diagram is valid for the grammar or not, and returns a production instance sequence for a valid diagram.