Cause Effect Graphing Example in Software Engineering
Question: There are two columns: col1 and col2. The characters allowed in col1 are ‘a’ or ‘b’. The characters allowed in col2 are digits 0-9. A file is updated if both the columns i.e. col1 and col2 are correct. If col1 is incorrect, message ‘X’ is displayed and if col2 is incorrect, message ‘Y’ is displayed. Draw the cause-effect graph for the given problem.
Following steps are performed to create a cause-effect graph:
1. Identify the causes:
2. Identify the effects:
3. Create nodes for all the causes and effects:
4. Use AND, NOT, OR and Identity functions to establish links between causes and effects:
1. e1 is obtained from c1, c2 and c3 in the following manner:
2. e2 is obtained from c1 and c2 in the following manner:
3. e3 is obtained from c3 in the following manner:
5. Add constraints to the graph, if any:
Exclusive constraint (or E-constraint) exists between c1 and c2 causes because at one point of time, only one of them can be 1 i.e., they cannot be 1 simultaneously. Hence, E-constraint is applied between them. The graph shown above is the final cause-effect graph obtained for the given problem.