Assignment 2 Solution

Total: 40 points




Value 10 points




Develop software specifications for a simple e-shopping system using the formalism of finite state machines. Consider some selected functionality. Make appropriate assumptions.



Note: there could be a variety of possible solutions; there is nothing wrong about that. Your answer will be evaluated on a basis of its completeness and correctness (taking into consideration the assumptions you have made).




Value 10 points




2.Suggest a collection of test cases to test a procedure finding a maximum of three integer




numbers




maxofThreeNumbers(int n1, int n2, int n3)




Consider (i) exhaustive testing and (ii) error guessing.




3.(i) Suppose that an application has n inputs (variables) and each variable partitions its input space in m equivalence classes. Determine the number of equivalence classes. How many tests do you require. Could be the number of tests made lower? Do detailed calculations for n =10 and m =10.




a system invokes function S if the reading of a given sensor is within the [a, b] or [c, d], b <c. The entire range of possible values is [-50, 50]. Identify equivalence classes. List a collection of tests.



generalize the problem in (ii) by considering that there are two sensors where the function is invoked for the sensors’ readings are in [ai, bi] or [ci, di], bi <ci, i=1, 2. How many test cases do you require here.



Value 10 points




4. Consider a 3-dimensional input domain described as




W = [0, 10] × [-5, 20] × [0, 7]




(viz. there are 3 input variables assuming values in the corresponding intervals). In this domain there are three equivalence classes




W1= {(x, y, z) | max (|x-1|, |y-1|, |z-1|) ≤ e}







1 of 2




W2= {(x, y, z) | max (|x-5|, |y-10|, |z-4|) ≤ e}




W3 = W-W1-W2




where e is a certain positive number. What should be possible values of e so that these equivalence classes form a partition?









































































































































































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