武汉大学遥感院复试上机练习(节选)

1、精品文档现有一数组， 其元素值见文件test.txt ，要求通过编程的方法求出这组数中值最大的元素、值最小的元素和中值元素。结果通过编程的方法写入文本文件中输出。#include #include usingnamespace std;intmain()intnum;ifstreamfilein(机试复习 2004testtest.txt);if(!filein)cout num;int*data =new int num;for ( inti = 0; i datai;filein.close();intswap;for ( inti = 0; i num-1;i+)for ( intj =

2、 i + 1; j dataj)swap = datai; datai = dataj;dataj = swap;elsecontinue;/冒泡法排序ofstreamfileout(机试复习 2004testtest2.txt);if(!fileout)cout cannot open the file!;return0;fileout max: datanum-1 endl;fileout min: data0 endl;fileout medium: datanum/2 endl;fileout.close();delete data,data=NULL;return1;.精品文档编写调

3、试程序从磁盘的数据文件“SourceData.txt ”中读入 10000 个数据，先理解为125 80的矩阵， 使用卷积矩阵1 进行卷积， 再理解为100100 的矩阵， 使用卷积矩阵2 进行卷积。0010001001210151121621a11a12a1nb11b12b1k01210010a21a22a2nb21b22b2 k 0lk01 c0 0 alii , jkbijijjii , jj卷积矩阵 1ii 1 jj 122am1bl1bl 2blkam2amn卷积矩阵 2例：由卷积模板B (3 3)对 A 矩阵 (56)进行卷积得到结果矩阵Ca11a12a13a14a15a16a21

4、a22a23a24a25a26a31a32a33a34a35a36b11b12b13a41a42a43a44a45a46b21b22b23a51a52a53a54a55a56b31b32b33BAC 中的元素 c33 为：c33a22 b11 a23 b12 a24 b13 a32 b21 a33 b22 a34 b23 a42 b31 a43 b32 a44 b33#include #include usingnamespace std;intmain()int*data =new int 10000;ifstreamfilein(机试复习 2005testSourceData.txt);i

5、f(!filein)cout cannot open the file!;return0;for ( inti = 0; i datai;filein.close();intMat133 = 0, -1, 0, -1, 5, -1, 0, -1, 0 ;intMat255 = 0, 0, -1, 0, 0, 0, -1, -2, -1, 0, -1, -2, 16, -2, -1,0, -1, -2, -1, 0, 0, 0, -1, 0, 0 ;.精品文档intMatrix112580, MatrixNew112580 = 0 ;intMatrix2100100, MatrixNew2100

6、100 = 0 ;intk = 0;for(inti = 0; i 125; i+)for(intj = 0; j 80; j+)Matrix1ij = datak;k+;k = 0;for ( inti = 0; i 100; i+)for ( intj = 0; j 100; j+)Matrix2ij = datak;k+;for(inti = 1; i 124; i+)for(intj = 1; j 79; j+)for( intm = -1; m = 1; m+)for( intn = -1; n = 1; n+)MatrixNew1ij += Matrix1i + mj + n *

7、Mat1m + 1n + 1;for(inti = 2; i 99; i+)for(intj = 2; j 99; j+)for( intm = -2; m = 2; m+)for( intn = -2; n = 2; n+)MatrixNew2ij += Matrix2i + mj + n * Mat2m + 2n + 2;ofstreamfileout(机试复习 2005testtest2.txt);if(!fileout)cout cannot open the file!;return 0;for( inti = 1; i 124; i+)for (intj = 1; j 79; j+

8、)fileout MatrixNew1ij ; fileout endl;fileout.close();deletedata,data= NULL;return1;.精品文档（ 1）利用随机函数rand()生成 (0， 1)区间的 100 个均匀分布随机数；提示： 首先利用“ srand(unsigned)time(NULL)”语句设置产生随机数的开始点（需要包含 time.h 头文件）；产生随机数的函数为 rand() ，为了将该随机数转换为（ 0， 1）范围内的数，利用“ rand()*1.0/RAND_MAX ”可实现此目的。（ 2）利用正态分布随机数的产生函数生成正态分布随机数。正态

9、分布随机数生成函数如下：y2lnxcos2 x *0.3+1（ 3）计算出100 个正态分布随机数y 的均值和方差，计算公式如下：nn2n2xxi /n ，2(/ n) - (xi / n)xii1i1i1其中，自变量x 即为 100 个均匀分布的随机数。#include #include #include #include #definePI 3.1415926usingnamespace std;intmain()double *data = new double 100;srand(unsigned )time( NULL);for(inti = 0; i 100; i+)datai =

10、 rand()*1.0 /RAND_MAX;double *data2 = new double 100;for(inti = 0; i 100; i+)data2i = 1 + 0.3*cos(2 *PI*datai)*sqrt(-2 * log(datai);double average = 0, variance = 0;for(inti = 0; i 100; i+)average += datai;variance += datai * datai;average /= 100;variance = variance/100 - average*average;/ 输出略delete

11、 data, data =NULL;delete data2, data2 =NULL;return1;.精品文档题目：已知某多光谱遥感影像一个样区的数据。阵。计算公式如下 :1）均值向量 :miM m1m2. mnT2）协方差矩阵 :11121n式 中 :分别计算该样区数据的均值向量和协方差矩1 N1xikN k 021222 nxik表ij示第 in1n2nn个波段样区的第k 个像元值， N 为样区像元总个数。1 N 1( xikmi )( x jkmj )N k 0multispectral.h中：#include #include usingnamespace std;/=计算多光谱影

12、像每个波段的均值/average: 输出每个波段的均值/num:每个波段的像元总数/band: 每个波段的波段数/data: 多光谱影像的像素值/=void Average( double *average,intnum,intband,vector *data);/=说明略/=void Matrix( vector *matrix,double *average,vector *data,intband, intnum);Multispectral.cpp中：#includemultispectral.hvoidAverage(double * average , intnum, int b

13、and,vector * data )for(inti = 0; i band; i+)average i = 0;for(inti = 0; i num; i+)for( int j = 0; j band; j+)average j += ( double ) data ji /num; voidMatrix(vector * matrix, double * average , vector * data , int band, int num)for(inti = 0; i band; i+).精品文档for(intj = 0; j band; j+)matrix i.push_bac

14、k(0);for(inti = 0; i band; i+)for(intj = 0; j band; j+)for ( intk = 0; k num; k+)matrix ij += (double ) data ik -average i)*( double ) data jk -average j) /num;主函数中：#include #include #include #include multispectral.husingnamespace std;intmain()intband, num;ifstreamfilein(机试复习 2006data.txt); / 判断略fil

15、ein band;filein num;vector *data= new vectorband;intcount;for(inti = 0; i band; i+)for(intj = 0; j count;datai.push_back(count);filein.close();double *average =new double band;vector *matrix =new vector num;Average(average, num, band, data);Matrix(matrix, average, data, band, num);delete data, data

16、=NULL;delete matrix, matrix =NULL;delete average, average =NULL;/ 输出略return1;外包矩形的概念如下图所示：（点落在内部和边缘上）外包矩形.多边形精品文档用编制的程序判断哪些点落在矩形外包内部，输出落在外包内的点号。#include #include #include usingnamespace std;structPOINTdouble x; double y;POINT() memset( this , 0,sizeof ( POINT); ;intmain()int num;ifstreamfilein(机试复习

17、2007test.txt);if(!filein)cout num;vector data;POINTpoint;for( inti = 0; i point.x;filein point.y;data.push_back(point);filein.close();double xmax = data0.x, xmin = data0.x, ymax = data0.y, ymin = data0.y;for( inti = 1; i xmax)xmax = datai.x;if(datai.xymax)ymax = datai.y;if(datai.yymin)ymin = datai.y

18、;cout 内部点有： ;.精品文档for ( inti = 0; i num; i+)if(datai.x != xmax&datai.x != xmin&datai.y != ymax&datai.y != ymin)cout i + 1 ;cout endl;return1;程序改：（将判断点放在文件中，以点名（字符），x， y 方式储存）structPOINTJudgedouble x;double y;char name10;POINTJudge()x = 0.0;y = 0.0;ifstreamfilein2(机试复习 2007 外包矩形欲判断点 .dat);if(!filein2

19、)cout cannot open the file!;return0;vector record;while (!filein2.eof()POINTJudgejugde;filein2 jugde.xjugde.y;if(jugde.x xmin&jugde.y ymin)record.push_back(jugde);filein2.close();cout 内部点有： ;for ( inti = 0; i record.size(); i+)cout recordi.x recordi.y endl ;cout endl;题目：编程统计某专

20、业的一门课程考试成绩的最高分、最低分、平均分以及考试.精品文档成绩分布的 均方差。说明：均方差计算公式如下：X 22XXNNX ：考试成绩；N：成绩总个数#include#include#includeusingnamespace std;intmain()int num = 0;double max = 0, min = 100, sum1 = 0, sum2 = 0;ifstreamfilein(新建文件夹 2008 年score.txt);if(!filein)cout num;double *data =new double num;for ( inti = 0; i datai;if

21、(dataimax)max = datai;if(datai min)min = datai;sum1 += datai;sum2 += datai * datai;filein.close();doubleaverage = 0.0, jun = 0.0;average = (double )sum1 / num;jun = sqrt(double )sum2 / num - average*average);ofstream fp2(机试复习 2008result.txt);if(!fp2)cout cannot open the file!;return0;fp2 最高分为 max en

22、dl 最低分为 min endl;fp2 平均分为 average endl 均方差为 jun endl;fp2.close();delete data,data=NULL;return1;试题：文件 test.txt 中存贮了一串字符串， 请统计该文件中各字母出现的次数（字.精品文档母的大小写不加区分，如 a与A算同一字母，标点符号不统计） ，并按出现次数的多少由高到低进行排列输出 ，最后将字母及出现次数的排列写入 result.txt 文件中。#include #include #include usingnamespace std;structalpint num;char d;alp(

23、) memset(this , 0,sizeof ( alp ); ;intmain()ifstreamfp(机试复习 2009source.txt);char data3000;/char *data =new char3000;intal26 = 0 ;intw = 0;while (!fp.eof()dataw = fp.get();w+;fp.close();for ( intj = 0; j = 0 & dataj - 65 = 0 & dataj - 97 = 25)aldataj - 97+;vector alph;alp me, ma;for ( into = 0; o 26;

24、 o+)me.d = A + o; me.num = alo;alph.push_back(me);for ( inti = 0; i 25; i+)for ( intj = i + 1; j alphj.num)ma = alphi;alphi = alphj;alphj = ma;for ( into = 0; o 26; o+)cout alpho.d alpho.num endl;/delete data,data=NULL;输出略return1;.精品文档题目：猫让 10 只老鼠站成一圈，它决定每数到第 n 只老鼠就吃掉，请输出最后剩下的老鼠的位置#include#includevoid main()int i, j, id; int num, l;printf( 请输入老鼠的个数： n ); scanf( %d, &num);printf( 请输入间隔 ( 范围：大于0 且小于老鼠个数 ) ：n );scanf( %d, &l);int*p;p = ( int*)malloc(sizeof ( int )*num);for (i