Test vector

In computer science and engineering, a test vector is a set of inputs provided to a system in order to test that system. In software development, test vectors are a methodology of software testing and software verification and validation.

Rationale

In computer science and engineering, a system acts as a computable function. An example of a specific function could be $y=f(x)$ where $y$ is the output of the system and $x$ is the input; however, most systems' inputs are not one-dimensional. When the inputs are multi-dimensional, we could say that the system takes the form $y=f(x_1,x_2,...)$ ; however, we can generalize this equation to a general form $Y=C(X)$ where $Y$ is the result of the system's execution, $C$ belongs to the set of computable functions, and $X$ is an input vector. While testing the system, various test vectors must be used to examine the system's behavior with differing inputs.

Example

For example, consider a login page with two input fields: a username field and a password field. In that case, the login system can be described as:

$y=L(u,p)$

with $y\in \{true,false\}$ and $u,p\in \{String\}$, with $true$ designating login successful, and $false$ designating login failure, respectively.

Making things more generic, we can suggest that the function $L$ takes input as a 2-dimensional vector and outputs a one-dimensional vector (scalar). This can be written in the following way:-

$Y=L(X)$

with $X=[x_1,x_2]=[u,p];Y=[y_1]$

In this case, $X$ is called the input vector, and $Y$ is called the output vector.

In order to test the login page, it is necessary to pass some sample input vectors $\{X_1,X_2,X_3,...\}$. In this context $X_i$ is called a test vector.

Alternatively, the concatenation of $X$ and $Y$, e.g., $[x_1,x_2,y_1]$, can be called a test vector.

See also

• Automatic test pattern generation

References

• Test Vector Guidelines. [1]
• Test Vector Considered Harmful. [2]