Row Equivalence Method for State Minimization is a very simple technique to reduce number of states of an FSM. In the row equivalence method, it is checked that rows of a state table are equivalent or not. Here, a comparatively strict definition of state equivalence is used. The conditions for two states and to be equivalent are
- The outputs must be same for both the states.
- The -successors must be same for all the input conditions.
Row Equivalence Method is explained here with the help of the state table shown in Table 1. Here, states and can be said equivalent as their output is same and their -successors are also same. Similarly, the states , and are equivalent. Thus using this simple state minimization technique the state table is reduced to the state table as shown in Table 2. Here, is written for states and . Similarly, is written for states , and .
Row Equivalence Method is a simple technique for state minimization but it does not always lead to optimized number of states.