matlab扩展编程里面的初始化问题

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function hmm = inithmm(samples, M)


K = length(samples); %语音样本数
N = length(M); %状态数
hmm.N = N;
hmm.M = M;


% 初始概率矩阵
hmm.init    = zeros(N,1);
hmm.init(1) = 1;


% 转移概率矩阵
hmm.trans=zeros(N,N);
for i=1:N-1
hmm.trans(i,i)   = 0.5;
hmm.trans(i,i+1) = 0.5;
end
hmm.trans(N,N) = 1;


% 概率密度函数的初始聚类
% 平均分段
for k = 1:K
T = size(samples(k).data,1);
samples(k).segment=floor([1:T/N:T T+1]);
end


%对属于每个状态的向量进行K均值聚类,得到连续混合正态分布
for i = 1:N
%把相同聚类和相同状态的向量组合到一个向量中
vector = [];
for k = 1:K
seg1 = samples(k).segment(i);
seg2 = samples(k).segment(i+1)-1;
vector = [vector ; samples(k).data(seg1:seg2,:)];
end
mix(i) = getmix(vector, M(i));
end


hmm.mix = mix;


function mix = getmix(vector, M)


[mean esq nn] = kmeans(vector,M);


% 计算每个聚类的标准差, 对角阵, 只保存对角线上的元素
for j = 1:M
%ind = find(j==nn);
    ind = find(j==mean);
tmp = vector(ind,:);
var(j,:) = std(tmp);
end


% 计算每个聚类中的元素数, 归一化为各pdf的权重
weight = zeros(M,1);
for j = 1:M
%weight(j) = sum(find(j==nn));
    weight(j) = sum(find(j==mean));
end
weight = weight/sum(weight);


% 保存结果
mix.M      = M;
mix.mean   = esq; % M*SIZE
mix.var    = var.^2; % M*SIZE
mix.weight = weight; % M*1