蟻の群のアルゴリズムは最短の経路のコードを求めます
4807 ワード
%%
%
clear all
clc
%
t0 = clock;
%
% :B,C
citys=xlsread('Chap9_citys_data.xlsx', 'B2:C53');
%%
n = size(citys,1);
D = zeros(n,n);
for i = 1:n
for j = 1:n
if i ~= j
% ,
D(i,j) = sqrt(sum((citys(i,:) - citys(j,:)).^2));
else
D(i,j) = 1e-4; % ( 0 0)
end
end
end
%%
m = 75; %
alpha = 1; %
beta = 5; %
vol = 0.2; % (volatilization)
Q = 10; %
Heu_F = 1./D; % (heuristic function)
Tau = ones(n,n); %
Table = zeros(m,n); %
iter = 1; %
iter_max = 100; %
Route_best = zeros(iter_max,n); %
Length_best = zeros(iter_max,1); %
Length_ave = zeros(iter_max,1); %
Limit_iter = 0; %
%%
while iter <= iter_max
%
start = zeros(m,1);
for i = 1:m
temp = randperm(n);
start(i) = temp(1);
end
Table(:,1) = start;
%
citys_index = 1:n;
%
for i = 1:m
%
for j = 2:n
tabu = Table(i,1:(j - 1)); % ( )
allow_index = ~ismember(citys_index,tabu); % 1( )
allow = citys_index(allow_index); %
P = allow;
%
for k = 1:length(allow)
P(k) = Tau(tabu(end),allow(k))^alpha * Heu_F(tabu(end),allow(k))^beta;
end
P = P/sum(P);
%
Pc = cumsum(P); % 2( )
target_index = find(Pc >= rand);
target = allow(target_index(1));
Table(i,j) = target;
end
end
%
Length = zeros(m,1);
for i = 1:m
Route = Table(i,:);
for j = 1:(n - 1)
Length(i) = Length(i) + D(Route(j),Route(j + 1));
end
Length(i) = Length(i) + D(Route(n),Route(1));
end
%
if iter == 1
[min_Length,min_index] = min(Length);
Length_best(iter) = min_Length;
Length_ave(iter) = mean(Length);
Route_best(iter,:) = Table(min_index,:);
Limit_iter = 1;
else
[min_Length,min_index] = min(Length);
Length_best(iter) = min(Length_best(iter - 1),min_Length);
Length_ave(iter) = mean(Length);
if Length_best(iter) == min_Length
Route_best(iter,:) = Table(min_index,:);
Limit_iter = iter;
else
Route_best(iter,:) = Route_best((iter-1),:);
end
end
%
Delta_Tau = zeros(n,n);
%
for i = 1:m
%
for j = 1:(n - 1)
Delta_Tau(Table(i,j),Table(i,j+1)) = Delta_Tau(Table(i,j),Table(i,j+1)) + Q/Length(i);
end
Delta_Tau(Table(i,n),Table(i,1)) = Delta_Tau(Table(i,n),Table(i,1)) + Q/Length(i);
end
Tau = (1-vol) * Tau + Delta_Tau;
% 1,
iter = iter + 1;
Table = zeros(m,n);
end
%%
[Shortest_Length,index] = min(Length_best);
Shortest_Route = Route_best(index,:);
Time_Cost=etime(clock,t0);
disp([' :' num2str(Shortest_Length)]);
disp([' :' num2str([Shortest_Route Shortest_Route(1)])]);
disp([' :' num2str(Limit_iter)]);
disp([' :' num2str(Time_Cost) ' ']);
%%
figure(1) %
plot([citys(Shortest_Route,1);citys(Shortest_Route(1),1)],... % Matlab
[citys(Shortest_Route,2);citys(Shortest_Route(1),2)],'o-');
grid on
for i = 1:size(citys,1)
text(citys(i,1),citys(i,2),[' ' num2str(i)]);
end
text(citys(Shortest_Route(1),1),citys(Shortest_Route(1),2),' ');
text(citys(Shortest_Route(end),1),citys(Shortest_Route(end),2),' ');
xlabel(' ')
ylabel(' ')
title(['ACA ( :' num2str(Shortest_Length) ')'])
figure(2)
plot(1:iter_max,Length_best,'b')
legend(' ')
xlabel(' ')
ylabel(' ')
title(' ')
%--------------------------------------------------------------------------
%%
% 1. ismember , 0-1 ;
% 2. cumsum , A=[1, 2, 3, 4, 5], cumsum(A)=[1, 3, 6, 10, 15]。
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