A state diagram can be converted to equations by writing an equation for each state and each transition.
A sample set of equations seen in See State Transition equations for the traffic
light example, see a traffic light state diagram.
Each state and the transition must be assigned a unique variable name. (Note: It is a
good idea to note these on the diagram)

These are then used to write equations for the diagram.
The transition equations are written by looking at each state, and then determining which transitions will end this state.
For example, if ST1 is true, and crosswalk
button S1 is pushed, and S2 is not, then transition T1 will be true. The state equations corresponding to the state equations in the previous State Equation
method, except that they now only refer to transitions. Recall, the
basic form of these equations is that the State will be where it is already on, or it is turned on by a transition. The State will be off if the exiting transition occurs. In this example the first scan had his own transition, but it could also have been put into the equation for T4.
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