1. A method of translation of a chart associated with a graphical modeling environment into an input/output-extended finite automata (I/O-EFA) model, the method comprising: receiving a representation of the chart; processing the representation of the chart with a computing device by (a) representing atomic models for each individual state of the chart, (b) applying composition rules to interconnect the atomic models while preserving state execution and transition behaviors to obtain the I/O-EFA model.