信息论实验报告

1、信息论实验报告学生： 班级：学号：实验一 香农编码一、 程序设计的流程图开始 输入N输入信源概率X(N)由大到小排序求累加概率累加概率转为二进制确定码长Ki求码字输出码字结束二、程序清单#include <iostream>#include<math.h>#include<string>using namespace std;void s *x,double *y);int main() int N; cout<<"输入信源个数"<<endl; cin>>N; double SN; /注意变量在数组中的

2、影响 cout<<"输入信源概率"<<endl; for(int i=0;i<N;i+) cin>>Si; for(int i=0;i<N;i+) for(int j=i;j<N;j+) if(Si<Sj) swap(Si,Sj); int nmN; for(int i=0;i<N;i+) nmi=int(-(log(Si)/log(2)+1; if(nmi=(-(log(Si)/log(2)+1) nmi-; double AAN; AA0=S0; for(int i=1;i<N;i+ ) AAi=A

3、Ai-1+Si; string MMN; for(int i=0;i<N;i+) double tem=0; double aa=AAi; for(int j=0;j<N;j+) tem=aa*2; if(tem>1) MMi+='1' aa=tem-1; else MMi+='0' aa=tem; string BBN; for(int i=0;i<N;i+) for(int j=0;j<nmi;j+) BBi+=MMij; cout<<"输出编码"<<endl; for(int i=0

4、;i<N;i+) cout<<BBi<<endl;void s &x,double &y) double a; a=x; x=y; y=a;实验二.费洛编码.一、 流程图 开始输入信源个数n输入信源符号sing【i】输入信源符号概率平p【i】按p【i】从小到大排序N-1>=1? N调用fano（）进行编码 Y编码输出结束二、程序清单#include <iostream>#include<string>#include<math.h>using namespace std;void dw(int n,int

5、H,int W,double *si,string *m);int main() int N; cout<<"输入信源个数"<<endl; cin>>N; double SN; cout<<"输入信源概率"<<endl; for(int i=0;i<N;i+) cin>>Si; for(int i=0;i<N;i+) for(int j=i;j<N;j+) if(Si<Sj) double a; a=Si; Si=Sj; Sj=a; string MMN; d

6、w(N,0,N-1,S,MM); cout<<"输出编码"<<endl; for(int i=0;i<N;i+) cout<<MMi<<endl;void dw(int n,int H,int W,double *si,string *m ) double sum=0,sm=0; int a1=W-H; if(a1>=1) for(int j=H;j<=W;j+) sum+=*(si+j); double bn; for(int i=H;i<=W;i+) sm+=*(si+i); bi=fabs(2*s

7、m-sum)/sum; int ZH; double a=bH; for(int i=H;i<=W;i+) if(bi<=a) a=bi; ZH=i; for(int i=H;i<=W;i+) if(i<=ZH) mi+='0' else mi+='1' int nn=n;double *ss;ss=si; string *mm;mm=m; if(ZH=H) dw(nn,ZH+1,W,ss,mm); else if(ZH=W-1) dw(nn,H,ZH,ss,mm); else dw(nn,H,ZH,ss,mm); dw(nn,ZH+1,

8、W,ss,mm); 实验三.霍夫曼 开始一、程序流程图输入lettersStrcmp（“%是”，是） 否 是计算字符个数与出现次数I+输出letersI<cnt？ 是 否条用霍夫曼编码结束二、 程序清单#include<iostream>#include<string>using namespace std; struct HNode double weight; int parent; int lchild; int rchild;void HuffmanTree(HNode *HuffNode,int n,double *si,string *m);int h

9、c(string m);void nv(string *m,int n);int main() int N; cout<<"输入信源个数"<<endl; cin>>N; double *S=new doubleN; cout<<"输入信源概率"<<endl; for(int i=0;i<N;i+) cin>>Si; string *MM=new stringN; for(int i=0;i<N;i+) for(int j=i;j<N;j+) if(Si<Sj)

10、 double a; a=Si; Si=Sj; Sj=a; HNode *node=new HNode2*N-1; HuffmanTree(node,N,S,MM); nv(MM,N); cout<<"输出编码"<<endl; for(int i=0;i<N;i+) cout<<MMi<<endl;void HuffmanTree(HNode *HuffNode,int n,double *si,string *m) int i,j,x1,x2,c,p; float m1,m2; for (i=0;i<2*n-1;

11、i+) HuffNodei.weight=0; HuffNodei.parent=-1; HuffNodei.lchild=-1; HuffNodei.rchild=-1; for (i=0;i<n;i+) HuffNodei.weight=sii; for (i=0;i<n-1;i+) m1=m2=1; x1=x2=0; for (j=0;j<n+i;j+) if (HuffNodej.parent=-1&&HuffNodej.weight<m1) m2=m1; x2=x1; m1=HuffNodej.weight; x1=j; else if (Hu

12、ffNodej.parent=-1&&HuffNodej.weight<m2) m2=HuffNodej.weight; x2=j; HuffNodex1.parent=n+i; HuffNodex2.parent=n+i; HuffNoden+i.weight=HuffNodex1.weight+HuffNodex2.weight; HuffNoden+i.lchild=x1; HuffNoden+i.rchild=x2; for(i=0;i<n;i+) c=i; p= HuffNodec.parent; while(p!=-1) if(HuffNodep.lch

13、ild =c) mi+='0' else mi+='1' c=p; p=HuffNodec.parent; int hc(string m) int a=0; for(int i=0;mi!='0'i+) a+; return a;void nv(string *m,int n)char mnn; int b; for(int i=0;i<n;i+) b=hc(mi); for(int j=0;j<b;j+) mnj=mib-j-1; mi=mn; 实验四.信道一、程序流程图 开始均匀分布迭代计算器k=0C(K+1)输出结果K=k+1

14、结束否是三、 程序清单#include <stdlib.h>#include <iostream>#include <math.h>using namespace std;int main() int ni,no; int i,j; cout<<"输入信源个数"<<endl; cin>>ni; cout<<"输出信源个数"<<endl; cin>>no; double *Si=new doubleni; double *So=new doublen

15、o; cout<<"输入信源概率"<<endl; for (i=0;i<ni;i+) cin>>Sii; cout<<endl; /再输入信道转移概率矩阵/注意进行判断，某行如果总概率大于1，则出现错误应从新输入 cout<<"输入转移概率："<<endl; float *p; /转移条件概率 p=new float *ni; for (i=0;i<ni;i+) pi=new floatno; for (i=0;i<ni;i+) for (j=0;j<no;j

16、+) cin>>pij; for (i=0;i<ni;i+) float a=0; for (j=0;j<no;j+) a+=pij; if (a!=1.0) cout<<"输入数据有误，请检查后再次输入。"<<endl; float *pp; /后验概率 pp=new float *ni; for (i=0;i<ni;i+) ppi=new floatno; float C_Pre,C; /当前信道容量和前一次循环信道容量 C=10.0; double Pe=0.000001; /两次信道容量相差的阈值 int r=0

17、; /迭代次数 float *p_up; /计算第r+1次循环输入分布p_in分子 p_up=new floatni; float p_down; /计算第r+1次循环输入分布p_in分母 do r+;/求第r次循环反条件概率p_ij for (j=0;j<no;j+) Soj=0.0; for (i=0;i<ni;i+) Soj+=pij*Sii; if (Soj>0) for (i=0;i<ni;i+) ppij=Sii*pij/Soj; /p(xy)/w(y),p(xy)=p(y/x)*p(x) else for (i=0;i<ni;i+) ppij=0;

18、/求第r+1次循环输入分布p_in p_down=0.0; for (i=0;i<ni;i+) p_upi=0.0; for (j=0;j<no;j+) if (ppij>=0.000001) p_upi+=pij*log(ppij)/log(2.0); p_upi=pow(2.0,p_upi); p_down+=p_upi; for (i=0;i<ni;i+) Sii=p_upi/p_down; /求C(r+1) C_Pre=C; C=log(p_down)/log(2.0); cout<<"第"<<r<<&qu

19、ot;次的容量为："<<C<<endl; while (fabs(C-C_Pre)/C>Pe); cout<<"迭代的次数为："<<r<<endl;实验五.循环码一、程序流程图退出输入码长nSwitch（n）生成多项式系数矩阵输入校验位输入信源信息向量cUx（g，c，r，n）X=1？X(g,c,r,n)开始选择编码方式序号二、 程序清单#include<iostream>#include <stdlib.h>using namespace std;int N;void UX(

20、int *g,int *c,int r,int n);void X(int *g,int *c,int r,int n);int main() N=10; int i,n,m,t,r; int gN,cN; cout<<"*循环码编码方法（码长n<=10)*n"<<endl; cout<<"t输入码长n:"<<endl; cin>>m; n=m; switch(n)/求生成多项式 case 1 :cout<<"输入校验位r<=%d:,"<<

21、n-1<<endl; cin>>r; switch(r) case 0:g0=1;break; break; case 2 :cout<<"输入校验位r<=%d:"<<n-1<<endl; cin>>r; switch(r) case 0:g0=1;break; case 1:g0=1;g1=1;break; break; case 3 :cout<<"输入校验位r<=%d:"<<n-1<<endl; cin>>r; swi

22、tch(r) case 0:g0=1;break; case 1:g0=1;g1=1;break; case 2:g0=1;g1=1;g2=1;break; break; case 4 :cout<<"输入校验位r<=%d:"<<n-1<<endl; cin>>r; switch(r) case 0:g0=1;break; case 1:g0=1;g1=1;break; case 2:g0=1;g1=0;g2=1;break; case 3:g0=1;g1=1;g2=1;g3=1;break; break; case 5

23、 :cout<<"输入校验位r<=%d:"<<n-1<<endl; cin>>r; switch(r) case 0:g0=1;break; case 1:g0=1;g1=1;break; case 4:g0=1;g1=1;g2=1;g3=1;g4=1;break; break; case 6 :cout<<"输入校验位r<=%d:"<<n-1<<endl; cin>>r; switch(r) case 0:g0=1;break; case 1:g

24、0=1;g1=1;break; case 2:g0=1;g1=1;g2=1;break; case 3:g0=1;g1=0;g2=0;g3=1;break; case 4:g0=1;g1=0;g2=1;g3=0;g4=1;break; case 5:g0=1;g1=1;g2=1;g3=1;g4=1;g5=1;break; break; case 7 :cout<<"输入校验位r<=%d:"<<n-1<<endl; cin>>r; switch(r) case 0 :g0=1;break; case 1 :g0=1;g1=

25、1;break; case 3 :g0=1;g1=0;g2=1;g3=1;break; case 4 :g0=1;g1=1;g2=1;g3=0;g4=1;break; case 6 :g0=1;g1=1;g2=1;g3=1;g4=1;g5=1; g6=1;break; break; case 8 :cout<<"输入校验位r<=%d:"<<n-1<<endl; cin>>r; switch(r) case 0 :g0=1;break; case 1 :g0=1;g1=1;break; case 2 :g0=1;g1=0;

26、g2=1;break; case 3 :g0=1;g1=1;g2=1;g3=1;break; case 4 :g0=1;g1=0;g2=0;g3=0;g4=1;break; case 5 :g0=1;g1=1;g2=0;g3=0;g4=1;g5=1;break; case 6 :g0=1;g1=0;g2=1;g3=0;g4=1;g5=0; g6=1;break; case 7 :g0=1;g1=1;g2=1;g3=1;g4=1;g5=1;g6=1; g7=1;break; break; case 9 :cout<<"输入校验位r<=%d:"<<

27、n-1<<endl; cin>>r; switch(r) case 0 :g0=1;break; case 1 :g0=1;g1=1;break; case 2 :g0=1;g1=0;g2=1;break; case 3 :g0=1;g1=0;g2=0;g3=1;break; case 4 :g0=1;g1=0;g2=1;g3=0;g4=1;break; case 5 :g0=1;g1=1;g2=1;g3=1;g4=1;g5=1;break; case 6 :g0=1;g1=1;g2=0;g3=1;g4=0;g5=1; g6=1;break; case 7 :g0=1;

28、g1=0;g2=1;g3=1;g4=1;g5=1; g6=0;g7=1;break; case 8 :g0=1;g1=1;g2=1;g3=1;g4=1;g5=1;g6=1; g7=1;g8=1;break; break; case 10 :cout<<"输入校验位r<=%d:"<<n-1<<endl; cin>>r; switch(r) case 0 :g0=1;break; case 1 :g0=1;g1=1;break; case 2 :g0=1;g1=0;g2=1;break; / case 3 :g0=1;g1=

29、0;g2=0;g3=1;break; case 4 :g0=1;g1=1;g2=1;g3=1;g4=1;break; case 5 :g0=1;g1=0;g2=0;g3=0;g4=0;g5=1;break; case 6 :g0=1;g1=1;g2=0;g3=0;g4=0; g5=1;g6=1;break; case 8 :g0=1;g1=0;g2=1;g3=0;g4=1; g5=0;g6=1;g7=0;g8=1;break; case 9 :g0=1;g1=1;g2=1;g3=1;g4=1;g5=1; g6=1;g7=1;g8=1;g9=1;break; break; cout<<

30、;"生成多项式系数矩阵为（幂次从低到高）：n"<<endl; for(i=0;i<=n-1;i+) cout<<gi<<" "/生成多项式g(x) cout<<"输入信源信息向量c(%d位)：n"<<n-r<<endl; for(i=0;i<=n-r-1;i+) cin>>ci; cout<<"t*选择编码方式及命令*n"<<endl; cout<<"t 1：系统编码n"<<endl; cout<<"t 2：非系统编码n"<<endl; cout<<"t 3：退出程序！n"<<endl; cout<<"t*n"<<endl; cin>>t; switch(t) case 1 :X(g,c,r,n);break; case 2 :UX(g,c,