sfng.asv

无标度网络的生成模型

function SFNet = SFNG(Nodes, mlinks, seed)

seed = full(seed);
pos = length(seed);

%if (Nodes < pos) || (mlinks > pos) || (pos < 1) || (size(size(seed)) ~= 2) || (mlinks < 1) || (seed ~= seed') || (sum(diag(seed)) ~= 0)
%    error('invalid parameter value(s)');
%end

%if mlinks > 5 || Nodes > 15000 || pos > 15000
%    warning('Abnormally large value(s) may cause long processing time');
%end

rand('state',sum(100*clock));%%Resets it to a different state each time.

Net = zeros(Nodes, Nodes, 'single');
Net(1:pos,1:pos) = seed;%%生成一个0矩阵，在1到pos位置上放置seed
sumlinks = sum(sum(Net));%%计算网络中边的数量

while pos < Nodes
    pos = pos + 1;%%增加一个节点
    linkage = 0;%%连边是0
    while linkage ~= mlinks%%如果连边不等于mlinks
        rnode = ceil(rand * pos);%%现有节点邻接矩阵各元素值最大值取整
        deg = sum(Net(:,rnode)) * 2;%%计算每个节点的度
        rlink = rand * 1;%%随机概率
        if rlink < deg / sumlinks && Net(pos,rnode) ~= 1 && Net(rnode,pos) ~= 1
            Net(pos,rnode) = 1;
            Net(rnode,pos) = 1;
            linkage = linkage + 1;
            sumlinks = sumlinks + 2;
        end
    end
end

clear Nodes deg linkage pos rlink rnode sumlinks mlinks 
SFNet = Net;