Hi.
function y=calcul(n,t)
for j=1:t
for i=1:100
[yy,i1]=fungi(n,j);
point(i)=yy(j+1);
end;
y(j)=sum(point)/100;
end;
function [y,concern]=fungi(n,t)
% n- number of fungi
% t- number of steps
% y- max distance in each step
% concen- density of points at given distance
m1(1,1:n)=1:n;
m2(1,1:n)=(1:n)*0;
y(1)=0;
for i=1:t
alfa=rand(1,n)*pi;
d=randn(1,n);
m1(i+1,1:n)=m1(i,1:n)+(d.*cos(alfa));
m2(i+1,1:n)=m2(i,1:n)+(d.*sin(alfa));
if any(m2(i+1,:)<0)
xx=find(m2(i+1,:)<0);
for j=1:length(xx)
m2(i+1,xx(j))=-m2(i+1,xx(j));
end;
end;
y(i+1)=max(max(m2(i+1,:)),y(i));
end;
maxy=y(t+1);
deltay=maxy/(2*t);
pop=n;
pointotal=sum(sum(m2(1:t+1,:)<=(maxy)));
%pointotal-all points
ilosc(1)=n/pointotal;
for i=1:2*t
total=sum(sum(m2(1:t+1,:)<=((i/(2*t))*maxy)));
concern(i+1)=total-pop;
concern(i+1)=concern(i+1)/pointotal;
pop=total;
end;
subplot(2,1,1);
plot([1,n],[0,0],'k','LineWidth',2);
% hold on;
for i=1:length(m1(1,:))
plot(m1(:,1),m2(:,i),'-*','Color',[rand(1),rand(1),rand(1)]);
% hold on;
end;
xlabel('X');
ylabel('Y');
subplot(2,1,2);
plot([0:deltay:maxy],concern);
xlabel('distance');
ylabel('density');
% hold off;
pause(0.01);
