function [n, nospec, evenness] = comm(size,type, par_a,par_b,pool_size,ifplot)
% This function generates a community of the size 'size' from an abundance distribution
% and returns abundances and number of species

%ifplot: 1 linear, 2 logarithmic

d=distr(type, par_a,par_b,pool_size);
dx=cumsum(d);
n = zeros(pool_size,1);
for i=1:size
   r = rand(1);
   for j=1:pool_size
      if r<dx(j)
         n(j) = n(j)+1;
         break;
      end
   end
   
end
n = fliplr(sort(n)');

scrsz = get(0,'ScreenSize');

if (ifplot)
   figure('Position',[10 scrsz(4)/2-30 scrsz(3)/2 scrsz(4)/2-30]);
end

nospec=sum(n>0);
n1=n(1:nospec);
const=sum((log(n1)./nospec));
evenness = 1 - (2 / pi) * atan(sum((log(n1)-const).^2) ./ nospec)

if (ifplot == 1)
   plot(1:pool_size,[d*size;n]);
elseif (ifplot == 2)
   plot(1:pool_size,log([d*size;n]));
end
if (ifplot)
   figure('Position',[13*scrsz(4)/20 scrsz(4)/2-30 scrsz(3)/2 scrsz(4)/2-30]);
   bar(n);
   title(nospec);
end