隐马尔可夫链模型和例程（包括前向、gtIwQhy后向算法、Viterbi解码以及为了减少概率数值计算误差编写的对数PcKtVOD运算程序）-Hidden Markov chain model and routines (including forward, backward gtIwQhy algorithm, Viterbi decoding, and in order to reduce the probability of numerical computation error of th