
Test Generation
4.9 COVERING AND MIXED-LEVEL COVERING ARRAYS
4.9.1 COVERING ARRAYS
A covering array CA(N, k, s, t)isanN × k matrix in which entries are
from a finite set S of s symbols such that each N × t subarray contains
each possible t-tuple at least Î times. As in the case of orthogonal arrays,
N denotes the number of runs, k the number of factors, s the number of
levels for each factor, t the strength, and Î the index. While generating
test cases or test configurations for a software application, we use Î = 1.
Let us point to a key difference between a covering array and an
orthogonal array. While an orthogonal array OA(N, k, s, t) covers
each possible ...