function final = clumpRatio2d(M,str)

% Gives the ratio of the mean interindividual distance to the diameter of a group (the largest
% interindividual distance).  Input M is an array of individuals in the standard indexed form; str is the structural output determined by application of findGroups2d.


mIID = interIndivDist2d(M,str)
diam = diameter2d(M)
ans = mIID/diam