How to define attribute (in class diagram)as an array of four elements using Papyrus as a modelling environment?
Does that possible in Papyrus?
Here is the class:

How to edit the properties of attribute in the following properties view to represent an array of four elements??

It is much, much more easy.
If these elements belong ONLY here, use composition - filled diamond. If they can exist by themselves, use Aggregation - empty diamond.