Domain Testing: Divide and Conquer - Testing Education

Domain Testing
Identifying Variables of a Function and Their Characteristics
Phase I: Given a function, identify variables and their characteristics
To conduct domain testing you will need either written or verbal specification, which
includes code, or the product or prototype. If the product is available, you can do
exploratory testing on it to get yourself familiarized with the product and the domain.
The analysis to be done in this phase requires the following steps:
1. Identify variables.
2. Categorize variables.
3. Explore functionality of the function with respect to the identified variables.
4. Identify and analyze values taken by each variable.
5. Determine whether the identified variables are one-dimensional or multidimensional.
6. Determine whether the identified variables are of range type or enumerated type.
7. Determine whether each of the identified variables is linearizable or not.
Step 1: Identify variables
What is a variable?
In general a variable
• is something that varies or is prone to variation.
• is a quantity capable of assuming a set of values.
• is a symbol representing a quantity. For example, in the expression a 2 + b 2 =
c 2 , a, b, and c are variables.
• is the mathematical model for a characteristic observed or measured in an
experiment, survey, or observational study.
In the computing world, a variable is the name given to a space in the memory to
store a value of some data type. The variable names can be conveniently used to
access the values stored in the memory.
Step 2: Categorize variables
Now that we have identified some variables, let us categorize these variables.
What are the different kinds of variables?
• Input
• Output
© Sowmya Padmanabhan, 2003 1