public double getTotalArea() {
		double area = 0;
		for (StructureInterface interf:members) {
			area+=interf.getTotalArea();
		}
		return area/members.size();
	}
public double getTotalArea ( ) { double area = 0 ; for ( StructureInterface interf : members ) { area += interf . getTotalArea ( ) ; } return area / members . size ( ) ; }
Return the average buried surface area for this interface cluster
@return