图论模型---dijstra算法

1、目标:无指向or有指向的最短路径。

2、Matlab实现:

weight=    [0     2     8     1   Inf   Inf   Inf   Inf   Inf   Inf   Inf;
            2     0     6   Inf     1   Inf   Inf   Inf   Inf   Inf   Inf;
            8     6     0     7     5     1     2   Inf   Inf   Inf   Inf;
            1   Inf     7     0   Inf   Inf     9   Inf   Inf   Inf   Inf;
          Inf     1     5   Inf     0     3   Inf     2     9   Inf   Inf;
          Inf   Inf     1   Inf     3     0     4   Inf     6   Inf   Inf;
          Inf   Inf     2     9   Inf     4     0   Inf     3     1   Inf;
          Inf   Inf   Inf   Inf     2   Inf   Inf     0     7   Inf     9;
          Inf   Inf   Inf   Inf     9     6     3     7     0     1     2;
          Inf   Inf   Inf   Inf   Inf   Inf     1   Inf     1     0     4;
          Inf   Inf   Inf   Inf   Inf   Inf   Inf     9     2     4     0;];
[dis, path]=dijkstra(weight,1, 11)


dijkstra.m
function [min,path]=dijkstra(w,start,terminal)
n=size(w,1); label(start)=0; f(start)=start;
for i=1:n
   if i~=start
       label(i)=inf;
end, end
s(1)=start; u=start;
while length(s)<n
   for i=1:n
      ins=0;
      for j=1:length(s)
         if i==s(j)
            ins=1;
         end,  
      end
      if ins==0
         v=i;
         if label(v)>(label(u)+w(u,v))
            label(v)=(label(u)+w(u,v)); 
         f(v)=u;
         end, 
      end, 
   end   
v1=0;
   k=inf;
   for i=1:n
         ins=0;
         for j=1:length(s)
            if i==s(j)
               ins=1;
            end, 
         end
         if ins==0
            v=i;
            if k>label(v)
               k=label(v);  v1=v;
            end,  
         end,  
   end
   s(length(s)+1)=v1;  
   u=v1;
end
min=label(terminal); path(1)=terminal;
i=1; 
while path(i)~=start
      path(i+1)=f(path(i));
      i=i+1 ;
end
path(i)=start;
L=length(path);
path=path(L:-1:1);

3、输入数据格式:

    [0     2     8     1   Inf   Inf   Inf   Inf   Inf   Inf   Inf;
     2     0     6   Inf     1   Inf   Inf   Inf   Inf   Inf   Inf;
     8     6     0     7     5     1     2   Inf   Inf   Inf   Inf;
     1   Inf     7     0   Inf   Inf     9   Inf   Inf   Inf   Inf;
   Inf     1     5   Inf     0     3   Inf     2     9   Inf   Inf;
   Inf   Inf     1   Inf     3     0     4   Inf     6   Inf   Inf;
   Inf   Inf     2     9   Inf     4     0   Inf     3     1   Inf;
   Inf   Inf   Inf   Inf     2   Inf   Inf     0     7   Inf     9;
   Inf   Inf   Inf   Inf     9     6     3     7     0     1     2;
   Inf   Inf   Inf   Inf   Inf   Inf     1   Inf     1     0     4;
   Inf   Inf   Inf   Inf   Inf   Inf   Inf     9     2     4     0;]


    [0     8   Inf   Inf   Inf   Inf     7     8   Inf   Inf   Inf;
   Inf     0     3   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf;
   Inf   Inf     0     5     6   Inf     5   Inf   Inf   Inf   Inf;
   Inf   Inf   Inf     0     1   Inf   Inf   Inf   Inf   Inf    12;
   Inf   Inf     6   Inf     0     2   Inf   Inf   Inf   Inf    10;
   Inf   Inf   Inf   Inf     2     0     9   Inf     3   Inf   Inf;
   Inf   Inf   Inf   Inf   Inf     9     0   Inf   Inf   Inf   Inf;
     8   Inf   Inf   Inf   Inf   Inf   Inf     0     9   Inf   Inf;
   Inf   Inf   Inf   Inf     7   Inf   Inf     9     0     2   Inf;
   Inf   Inf   Inf   Inf   Inf   Inf   Inf   Inf     2     0     2;
   Inf   Inf   Inf   Inf    10   Inf   Inf   Inf   Inf   Inf     0;];

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转载自www.cnblogs.com/lilei0128/p/11099368.html