fun3.10=function(p,t){
+ X=matrix(0,nrow=p,ncol=t)
+ for(j in 1:t){
+ for(i in i:p){
+ X[i,j]=rnorm(1,0,1)
+ }
+ }
+ X
+ }
> fun3.10(10,10)
错误于`[<-`(`*tmp*`, i, j, value = -0.707581489904859) : 下标出界
>