[R] generate

[MacQueen, Don]

Or, to show the "power of the R language", so to speak, and assuming that
Dave is correct, there is no need to use a for() loop:

 xmat <- matrix( rnorm( 27*5, rep(mu,5), rep(sig,5) ) , nrow=27)

To verify that I've created the vectors in the right order, and converted
to a matrix in the right order, try this:

mu <- 1:27
sig <- rep(1,27)

x.matrix<-matrix(0,nrow=27,ncol=5)
for(i in 1:27){
#  x.matrix[i,j]<-rnorm(5,mu[i],sig[i])
  ## Dave's suggestion:
  x.matrix[i, ] <- rnorm(5,mu[i],sig[i])  # since 'j' doesn't exist
}

## loop not necessary:
xmat <- matrix( rnorm( 27*5, rep(mu,5), rep(sig,5) ) , nrow=27)


plot( rowMeans(x.matrix), rowMeans(xmat))
abline(0,1)

-- 
Don MacQueen

Lawrence Livermore National Laboratory
7000 East Ave., L-627
Livermore, CA 94550
925-423-1062





On 3/27/14 12:39 PM, "David Winsemius" <dwinsemius at comcast.net> wrote:

>
>On Mar 27, 2014, at 4:31 AM, IZHAK shabsogh wrote:
>
>> i try to generate 27*5  matrix of observation using the following code
>>but is given error
>> kindly assist and correct the problem
>> 
>> 
>> x1<-c(-1,0,1,-1,0,1,-1,0,1,-1,0,1,-1,0,1,-1,0,1,-1,0,1,-1,0,1,-1,0,1)
>> x2<-c(-1,-1,-1,0,0,0,1,1,1,-1,-1,-1,0,0,0,1,1,1,-1,-1,-1,0,0,0,1,1,1)
>> x3<-c(-1,-1,-1,-1,-1,-1,-1,-1,-1,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1)
>> mu<-50+5*(x1^2+x2^2+x3^2)
>> sig<-100+5*((x1-0.5)^2+x2^2+x3^2)
>> x.matrix<-matrix(0,nrow=27,ncol=5)
>> for(i in 1:27){
>
>Perhaps, instead:
>
> x.matrix[i, ]<-rnorm(5,mu[i],sig[i])  # since 'j' doesn't exist
>
>> x.matrix[i,j]<-rnorm(5,mu[i],sig[i])
>> }
>> 
>> 
>> Thanks
>> Ishaq
>> 	[[alternative HTML version deleted]]
>> 
>> ______________________________________________
>> R-help at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide
>>http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>
>David Winsemius
>Alameda, CA, USA
>
>______________________________________________
>R-help at r-project.org mailing list
>https://stat.ethz.ch/mailman/listinfo/r-help
>PLEASE do read the posting guide
>http://www.R-project.org/posting-guide.html
>and provide commented, minimal, self-contained, reproducible code.