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A regular polygon is a polygon which is equiangular (all angles are equal in measure) and equilateral (all sides have the same length).

Note the appearance of model information (like 'concave') from other logical contexts. In most UML tools one has the ability to choose to display or not display such information, to better reflect the immediate context. Often one has to return to "earlier" diagrams to find out what information has been introduced later and hide the display of information from "later" contexts (source sentences), at one's discretion.

Note also the use of the SysML Real.