信息與編碼實驗一

桂林電子科技大學(xué)數(shù)學(xué)與計算科學(xué)學(xué)院實驗報告院(系)數(shù)學(xué)與計算科學(xué)學(xué)號1200710218姓名韓尚莉成績課程名稱信息與編碼實驗實驗項目名稱實驗一信息熵的計算指導(dǎo)教師實驗室：06406實驗日期：2015年12月12日一，實驗?zāi)康膶⒁淮蠖斡⑽奈恼伦鳛橐y(tǒng)計的樣本文件對樣本文件進(jìn)行一維概率統(tǒng)計，并計算出信源熵及冗余度對樣本文件進(jìn)行二維概率統(tǒng)計，并計算出信源熵及冗余度二，實驗原理在進(jìn)行統(tǒng)計時，首先要在程序中打開文件，然后對文件中的字符讀入程序中，進(jìn)行統(tǒng)計。而在二維統(tǒng)計時，尤其要求對文件的指針操作要熟悉。如讀入“newspaper”時，應(yīng)該依次讀入“neewwssppaappeer”，而如果使用fgetc()等命令讀文件時，讀入的是“newspape”為了依次讀入“服ewwssppaappeer”，就要求在每次調(diào)入fgetc()等命令后，再將文件指針往后退一步，即要求學(xué)生能熟練使用fseek()命令進(jìn)行指針定位操作。三，使用儀器，材料計算機(jī)，VisualC++6.0四，實驗內(nèi)容與步驟(過程及結(jié)果截圖)首先，下載或者建立一個含有英文字母的txt文檔，接下來，編寫程序統(tǒng)計字符以及計算熵。一維：#include<stdio.h>#include<string.h>#include<math.h>#define_FILEPATH"F:\\xinhao與編碼\\0.txt"#define_ALAPHA_NUMBER((int)('z'-'a'+1))voidPrintStati(intarr[],intsize);intStati(constchar*filePath,intarr[]);floatEntropCompute(intarr[],intsum,intarrSize);intmain(){intarr[_ALAPHA_NUMBER*2]={0};intsampleSize=0;sampleSize=Stati(_FILEPATH,arr);PrintStati(arr,_ALAPHA_NUMBER*2);printf("\n");printf("samplesize:%d\n",sampleSize);printf("entrop:%f\n",EntropCompute(arr,sampleSize,_ALAPHA_NUMBER*2));return0;}voidPrintStati(intarr[],intsize){inti=0;while(i<size){if(i<_ALAPHA_NUMBER){printf("%c:%d",i+'a',arr[i]);}else{printf("%c:%d",i+'A'-_ALAPHA_NUMBER,arr[i]);}i++;}}intStati(constchar*filePath,intarr[]){FILE*pFile=NULL;charc;intsum=0;pFile二fopen(filePath,"rb");if(pFile==NULL){printf("failtoopenfile");return0;}while(1){c=fgetc(pFile);if(c==EOF){break;}if(c>='a'&&c<='z'){arr[c-'a']++;sum++;}elseif(c>='A'&&c<='z'){arr[_ALAPHA_NUMBER+c-'A']++;sum++;}}fclose(pFile);returnsum;}floatEntropCompute(intarr[],intsum,intarrSize){floatentrop=0.0F;inti=0;floatprobability=0;while(i<arrSize){if(arr[i]!=0){probability=(arr[i]*1.0F)/sum;entrop+=(-probability*(log(probability)/log(2)));}i++;}returnentrop;}運(yùn)彳丁結(jié)果：S3F:\xinha曰與編碼命名Lexe—OXl：7206b:1818c：2709d:3191e：12962f:1889g：1914h:5286i:7222j:61k:5541:5861Im：2665n：7108o:8408p:2169q：43r:6339s:6658t:10577u：3103v:1223w：1945x:I.33y：2687z：2A:155B:69C:89D:88E:60F:92G:2H:201:309J:66K:2L:1M:79N10:43P:2Q:0R:2S:17T:191U:1V:1W:28X:0Y:2Z:0I;amplesize:105056sntrop:4.240259'rocessexitedwithreturnvalue0'ressanykeytocontinue...二維：#include<stdio.h>#include<math.h>#include<stdlib.h>#defineNULL0intcharge(charc){intn;if(c>=65&&c<=90)c=c+32;if(c>+97&&c<=122){n=c-97;returnn;}elsereturn-1;}intmain(){intcount[26][26]={0};charzifu1,zifu2;inti,n,m,j;intsum=0;floatq,sum1=0;FILE*fp;

if((fp=fopen("F:\\xinhao與編碼\\0.txt","rb"))二二NULL){printf("can'topenfile!\n");exit(0);}while(!feof(fp)){zifu1=fgetc(fp);n=charge(zifu1);if(n!=-1){zifu2=fgetc(fp);m=charge(zifu2);if(m!=-1){count[n][m]++;fseek(fp,-1,1);}}}fclose(fp);for(i=0;i<26;i++)for(j=0;j<26;j++)sum=sum+count[i][j];printf("thenumberofallthecodeis%d\n",sum);q=(float)sum;for(i=0;i<26;i++)for(j=0;j<26;j++){if(j%3==0)printf("\n");printf("%c%c,%4d,%6.5f%%",i+97,j+97,count[i][j],count[i][j]*100/q);}printf("\n");for(i=0;i<26;i++)for(j=0;j<26;j++)if(count[i][j]));sum1=sum1+(float)((count[i][j]/q)*log10(1/(double)(count[i][j]/q))/log10((double)(2))printf("\n信息熵為：H(x)=%f\n",sum1);}運(yùn)彳丁結(jié)果：);1>1Z\shang.exeheni_unbero±alltJ^ieoccteis-門ri.rinririri%0.00000%n.nnnnn%u.uuucju%o.00000%u.uuuuu%o.00000%Ij.UUULiij%0.00000%n.nnnnn%o.uuuoo%0.00000%u.UUULJLJ%0.00000%Ij.OOuijij%0.00000%n.nnnnn%u.n.onnnn%U.UUULJLJ%o.00000%ij.UUULuj%0.00000%I-n-r-I--rn-T□n-.■!■-rn-T_Jr-.-I--r-I--r□I-behkn<l七-V工behkn蟲t.wubcfhk11aaaaabbbbbbbbbL:c:1---'_■-:-I-n-r-I--rn-T-Jn-Jr-rn-T_Jr-I-I--r-I--r-Jnnonoouo-M-on^.5UO.M-4noo4GSO'J6U4'JJ<L30.□□□□□%0.00000%n.nnnnn%□.uuuuu%0.00000?ou.uuuuu%o.00000%a.oooaawo.00000%n.nnnnnw□.AlLJlb%0.00000%u.uuuuu%0.00000%ij.'joOCuj%0.00033%n.nnnnn%□.uuuuu%口一onnno%U.bya<Lb%0.4SG37%0.01129%0.00000%EF:斶碼實驗W幅hang’ex巳xp,0,xs,0,Sxy,0,ya,Syd,Syg,Syj,0,ym,59,VP,12,ys,100,yv,0,yy,Sza,0,zd,0,格Sn0,部結(jié)結(jié)視本ES,本的字入0.00000%0.00000%0.00000%0.00000%0.00000%0.00000%0.00000%0.00000%0.08328%0.01694%0.14115%0.00000%0.00000%0.00000%0.00000%0.00000%0.00000%0.00000%RbK)o%驗，將含有中，進(jìn)行統(tǒng)0.00000%xq,0,xt,17,xw,0,xz,0,yb,0,ye,97,yhn0,yk,0,皿0,雙0,yt,1,yw,0,V瓦0,zb,0,ze,1,zh,0,zk,0,zn,0,段英I段英B^實驗對zz,0,0.00000%0.02400%0.00000%0.00000%0.00000%0.13691%0.00000%0.00000%0.00000%0.00000%0.00141%0.00000%0.00000%0.00000%0.00141%0.00000%0.00000%0.00000%0.00000%rn作為要統(tǒng)進(jìn)行一維0.00000%ri.□□□□□%0.00000%n.nnnno%u.uuuuu%0.00000%u.uuuuu%0.00000%u.Ijijuuij%n.nnnnn%u.ouuuo%0.44744%u.0.273S3%0.ij'jOOu%0.45440%n.nnnnn