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参考书《数据压缩导论(第4版)》 Page 100 5, 6
5、给定如表4-9所示的概率模型,求出序列a1a1a3a2a3a1 的实值标签。
求序列a1a1a3a2a3a1 的实值标签就是求序列113231的实值标签
Fx(k)=0, k≤0, Fx(1)=0.2, Fx(2)=0.5, Fx(3)=1, k>3.
l(0)=0, u(0)=0
1
l(1)= l(0)+(u(0)- l(0))*Fx(0)=0+(1-0)*0=0
u(1)= l(0)+(u(0)- l(0))*Fx(1)=0+(1-0)*0.2=0.2
11
l(2)= l(2)+(u(1)- l(1))*Fx(0)=0+(1-0)*0=0
u(2)= l(1)+(u(1)- l(1))*Fx(1)=0+(0.2-0)*0.2=0.04
113
l(3)= l(2)+(u(2)- l(2))*Fx(2)=0+(0.04-0)*0.5=0.02
u(3)= l(2)+(u(2)- l(2))*Fx(3)=0+(0.04-0)*1=0.04
1132
l(4)=l(3)+(u(3)-l(3))*Fx(1)=0.02+(0.04-0.02)*0.2=0.024
u(4)=l(3)+(u(3)-l(3))*Fx(2)=0.02+(0.04-0.02)*0.5 =0.03
11323
l(5)=l(4)+(u(4)-l(4))*Fx(2)=0.024+(0.03-0.024)*0.5=0.027
u(5)=l(4)+(u(4)-l(4))*Fx(3)=0.024+(0.03-0.024)*1=0.03
113231
l(6)=l(5)+(u(5)-l(5))*Fx(0)=0.027+(0.03-0.027)*0=0.027
u(6)=l(5)+(u(5)-l(5))*Fx(1)=0.027+(0.03-0.027)*0.2=0.0276
Tx(113231)= ( u(6) + l(6) )/2
=(0.0276+0.027)/2
=0.0273
6、对于表4-9所示的概率模型,对于一个标签为0.63215699的长度为10的序列进行解码。
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原文地址:http://www.cnblogs.com/oujintao/p/4818484.html