第二章2.1> x<-c(1,2,3);y<-c(4,5,6)> e<-c(1,1,1)> z<-2*x+y+e;z[1] 7 10 13> z1<-crossprod(x,y);z1 [,1][1,] 32> z2<-outer(x,y);z2 [,1] [,2] [,3][1,] 4 5 6[2,] 8 10 12[3,] 12 15 182.2(1) > A<-matrix(1:20,nrow=4);B<-matrix(1:20,nrow=4,byrow=T)> C<-A+B;C(2) > D<-A%*%B;D(3) > E<-A*B;E(4) > F<-A[1:3,1:3](5) > G<-B[,-3]2.3> x<-c(rep(1,5),rep(2,3),rep(3,4),rep(4,2));x2.4> H<-matrix(nrow=5,ncol=5)> for (i in 1:5)+ for(j in 1:5)+ H[i,j]<-1/(i+j-1)（1）> det(H)（2）> solve(H)（3）> eigen(H) 2.5> studentdata<-data.frame(姓名=c('张三','李四','王五','赵六','丁一')+ ,性别=c('女','男','女','男','女'),年龄=c('14','15','16','14','15'),+ 身高=c('156','165','157','162','159'),体重=c('42','49','41.5','52','45.5'))2.6> write.table(studentdata,file='student.txt')> write.csv(studentdata,file='student.csv')2.7count<-function(n){if (n<=0)print('要求输入一个正整数')else{repeat{if (n%%2==0)n<-n/2elsen<-(3*n+1)if(n==1)break}print('运算成功')}}第三章3.1首先将数据录入为 x。利用 data_outline 函数。如下> data_outline(x)3.2> hist(x,freq=F)> lines(density(x),col='red')> y<-min(x):max(x)> lines(y,dnorm(y,73.668,3.9389),col='blue')> plot(ecdf(x),verticals=T,do.p=F)> lines(y,pnorm(y,73.668,3.9389))> qqnorm(x)> qqline(x)3.3> stem(x)> boxplot(x)> fivenum(x)3.4> shapiro.test(x)> ks.test(x,'pnorm',73.668,3.9389) One-sample Kolmogorov-Smirnov testdata: xD = 0.073, p-value = 0.6611alternative hypothesis: two-sidedWarning message:In ks.test(x, "pnorm", 73.668, 3.9389) : ties should not be present for the Kolmogorov-Smirnov test这里出现警告信息是因为 ks 检验要求样本数据是连续的，不允许出现重复值3.5>x1<-c(2,4,3,2,4,7,7,2,2,5,4);x2<-c(5,6,8,5,10,7,12,12,6,6);x3<-c(7,11,6,6,7,9,5,5,10,6,3,10)> boxplot(x1,x2,x3,names=c('x1','x2','x3'),vcol=c(2,3,4))>windows()>plot(factor(c(rep(1,length(x1)),rep(2,length(x2)),rep(3,length(x3)))),c(x1,x2,x3))3.6> rubber<-data.frame(x1=c(65,70,70,69,66,67,68,72,66,68),+x2=c(45,45,48,4...
