MATLAB流量分配代码：寻找主路线和备用路线

是的，上述代码可以用MATLAB编写。以下是等效的MATLAB代码示例，用于解决分层为物理网络与逻辑网络的流量分配问题，找出主路线与备用路线。

% 定义图的类
classdef Graph < handle
    properties
        V;  % 节点数
        graph;  % 图的邻接矩阵
    end
    
    methods
        function obj = Graph(vertices)
            obj.V = vertices;
            obj.graph = zeros(obj.V, obj.V);
        end
        
        % 添加物理网络的边
        function addPhysicalEdge(obj, src, dest, capacity)
            obj.graph(src, dest) = capacity;
            obj.graph(dest, src) = capacity;
        end
        
        % 添加逻辑网络的边和需求流量
        function addLogicalEdge(obj, src, dest, demand)
            obj.graph(src, dest) = demand;
        end
        
        % Bellman-Ford算法，用于寻找最短路径
        function [dist, parent] = bellmanFord(obj, src, dest)
            dist = inf(1, obj.V);
            dist(src) = 0;
            parent = -ones(1, obj.V);
            
            for k = 1:obj.V-1
                for u = 1:obj.V
                    for v = 1:obj.V
                        if obj.graph(u, v) > 0 && dist(v) > dist(u) + obj.graph(u, v)
                            dist(v) = dist(u) + obj.graph(u, v);
                            parent(v) = u;
                        end
                    end
                end
            end
        end
        
        % 最小费用最大流算法
        function [maxFlow, totalCost] = minCostMaxFlow(obj, src, dest)
            maxFlow = 0;
            totalCost = 0;
            
            while true
                [dist, parent] = obj.bellmanFord(src, dest);
                
                if parent(dest) == -1
                    break;
                end
                
                flow = inf;
                v = dest;
                while v ~= src
                    flow = min(flow, obj.graph(parent(v), v));
                    v = parent(v);
                end
                
                maxFlow = maxFlow + flow;
                
                v = dest;
                while v ~= src
                    obj.graph(parent(v), v) = obj.graph(parent(v), v) - flow;
                    obj.graph(v, parent(v)) = obj.graph(v, parent(v)) + flow;
                    v = parent(v);
                end
            end
            
            % 计算总费用
            for u = 1:obj.V
                for v = 1:obj.V
                    totalCost = totalCost + obj.graph(v, u);
                end
            end
        end
        
        % 寻找主路线与备用路线
        function [mainRoute, backupRoute] = findRoutes(obj, src, dest, demand)
            % 执行最小费用最大流算法
            obj.minCostMaxFlow(src, dest);
            
            % 初始化主路线和备用路线
            mainRoute = [];
            backupRoute = [];
            
            for u = 1:obj.V
                for v = 1:obj.V
                    % 找到主路线上的边
                    if obj.graph(v, u) > 0
                        mainRoute = [mainRoute; [u, v]];
                    end
                    
                    % 找到备用路线上的边
                    if obj.graph(u, v) > 0
                        backupRoute = [backupRoute; [u, v]];
                    end
                end
            end
        end
    end
end

% 主程序
numPhysicalNodes = 5;
numLogicalNodes = 4;

g = Graph(numPhysicalNodes + numLogicalNodes);

% 添加物理网络的边和容量
g.addPhysicalEdge(1, 2, 10);
g.addPhysicalEdge(1, 3, 20);
g.addPhysicalEdge(2, 3, 30);
g.addPhysicalEdge(2, 4, 40);
g.addPhysicalEdge(3, 4, 50);
g.addPhysicalEdge(3, 5, 60);
g.addPhysicalEdge(4, 5, 70);

% 添加逻辑网络的边和需求流量
g.addLogicalEdge(numPhysicalNodes + 1, numPhysicalNodes + 2, 5);
g.addLogicalEdge(numPhysicalNodes + 1, numPhysicalNodes + 3, 7);
g.addLogicalEdge(numPhysicalNodes + 2, numPhysicalNodes + 4, 10);
g.addLogicalEdge(numPhysicalNodes + 3, numPhysicalNodes + 4, 8);

% 执行最小费用最大流算法，找出主路线和备用路线
[mainRoute, backupRoute] = g.findRoutes(1, numPhysicalNodes + 4, 30);

disp('主路线：');
for i = 1:size(mainRoute, 1)
    disp(['从节点', num2str(mainRoute(i, 1)), '到节点', num2str(mainRoute(i, 2))]);
end

disp('备用路线：');
for i = 1:size(backupRoute, 1)
    disp(['从节点', num2str(backupRoute(i, 1)), '到节点', num2str(backupRoute(i, 2))]);
end

MATLAB代码与Python代码非常相似，只是在MATLAB中需要注意索引从1开始。根据您的实际情况，您可以调整物理网络节点数、逻辑网络节点数、边、容量和需求流量，并使用MATLAB代码进行测试。