If we take a closer look at the main flow of events for the use case Start Simulation, we realize that the sequence of events may not be meaningful, unless we are at the right starting point of the use case. In the case that the weather data are provided as a text file, the right starting point for the simulation is when the weather file exists and is stored in the right directory. If there is no weather data file, then the simulation cannot be performed. In this case, we can say that the precondition for the use case Start Simulation is the following:

A valid weather data file is stored in the right directory of the system. A precondition is a statement that presents conditions under which the use case can be executed. In the case above, the precondition states that no use case can be executed if there is no weather data file or the file is not placed in the right directory.

0 0

Post a comment