The “has member” relationship

We may want to refer to all the buttons of the shirt. Each of the ten buttons is itself a class. In order to refer to a set of buttons, we must define a new class that represents the set. The “has member” relationship specifies the members of the set.

The class Set of all buttons of shirt has been defined as:

Set of all buttons of shirthas memberButton of collar band, Set of buttons of front band, Set of buttons of cuffs

This diagram shows all the “has member” relationships for the buttons.

button sets

In the FMA

The FMA also has sets. One example is the vertebrae:

Set of all vertebraehas member
Set of cervical vertebrae, Set of thoracic vertebrae,Set of lumbar vertebrae, Set of sacral vertebrae, Coccyx

Each of these sets of vertebrae is composed of individual vertebrae. For example:

Set of sacral vertebraehas member
First sacral vertebrae, Second sacral vertebrae,Third sacral vertebrae, Fourth sacral vertebrae, Fifth sacral vertebrae