By: Prof. Dr. Fazal Rehman | Last updated: November 12, 2022
Black Box – BVT on 3 Variables software testing
Suppose we have three variable x,y, and z to test.The range of x: 0 to 100The range of y :20 to 60The range of z : 80 to 100
X
y
z
Min
0
20
80
Min+
1
21
81
Nominal
50
40
90
Max-
99
59
99
Max
100
60
100
Figure: Testing points detected in Simple Boundary Value Testing.Black Box Boundary value testing
Total Test cases =(Number of variables * Number of testing points without nominal ) + (1 for Nominal)13=(3*4)+1
There are total 3 variables X,Y and Z
There are 4 possible values like min, min+, max- and max
1 is for nominal
Logic:When we make test cases, we will fix the nominal value of two variables and change the values of the third variable.For example
We will fix nominal values of X and Y and make a combination of these values with each value of Z variable.
Fix nominal values of X and Y are 50,40, and we will compare these two values with 80,81,90,99 and 100.
We will fix nominal values of Y and Z and will make a combination of these values with each value of X variable.
Fix nominal values of Y and Z are 40, 90, and we will make a combination of these two values with 0,1,50,99,100
We will fix nominal values of X and Z and will make a combination of these values with each value of Y variable.
Fix nominal values of X and Z are 50, 90 , and we will make combination of these two values with 20,21,40,59,60We can generate 13 test cases from both variables X, Y and Z
Test Case#
X,Y,Z
Test Case #
X,Y,Z
Test Case #
X,Y,Z
1
50,40,80
2
50,40,81
3
50,40,90
4
50,40,99
5
50,40,100
6
0,40,90
7
1,40,90
8
99,40,90
9
100,40,90
10
50,20,90
11
50,21,90
12
50,59,90
13
50,60,90
Figure: Test cases generated in Simple Boundary Value Testing using 3 variables.
