Matrix: Problem with the code

Charlotte: I ran your code because I wasn't clear on it and your way would
cause more matrices than the person requested.

I think the code below it, although not too short, does what the person
asked. Thanks though because I understand outer better now.

temp <- matrix(c(1,2,3,4,5,6),ncol=2)
print(temp)

#One of those more elegant ways:
print(temp)
outer(temp,1:p,'^')One of those more elegant ways:


# THIS WAY I THINK GIVES WHAT THEY WANT

sapply(1:ncol(temp), function(.col) {
 temp[,.col]^.col
})



On Fri, Jan 9, 2009 at  7:40 PM, Charlotte Wickham wrote:

One of those more elegant ways:
outer(x, 1:p, "^")

Charlotte

On Fri, Jan 9, 2009 at 4:24 PM, Sarah Goslee <sarah.goslee at gmail.com>
wrote:

Well, mat doesn't have any dimensions / isn't a matrix, and we don't
know what p is supposed to be. But leaving aside those little details,
do you perhaps want something like this:

    x<-c(23,67,2,87,9,63,8,2,35,6,91,41,22,3)
    p <- 5
    mat<- matrix(0, nrow=p, ncol=length(x))
    for(j in 1:length(x))
    {
        for(i in 1:p)
            mat[i,j]<-x[j]^i
    }

Two notes: I didn't try it out, and if that's what you want rather
than a toy example
of a larger problem, there are more elegant ways to do it in R.

Sarah

On Fri, Jan 9, 2009 at 6:42 PM, Bhargab Chattopadhyay
<bhargab_1 at yahoo.com> wrote:

Hi,


Can any one please explain why the following code doesn't work? Or can
anyone suggest an alternative.
Suppose
     x<-c(23,67,2,87,9,63,8,2,35,6,91,41,22,3)
      mat<-0;
      for(j in 1:length(x))
      {
         for(i in 1:p)
              mat[i,j]<-x[j]^i;
      }
  Actually I want to have a matrix with p columns such that each column
will have the elements of  x^(column#).

Thanks in advance.

Bhargab

--
Sarah Goslee
http://www.functionaldiversity.org