[R] Help with PCA

[Sarah Goslee]

Hi,

On Wed, Dec 28, 2011 at 7:54 AM, elisacarli21 <elisacarli21 at gmail.com> wrote:
> Dear all,
>
> I've  a correlation matrix with rows and columns headings.
> I've two questions:
>
> 1) How can i import it in R, setting first row as row heading and first
> column as column heading?

read.table, with the appropriate options. You can see what they are
by typing
?read.table
at an R prompt.

> 2) Which is the best principal component anlysis package in R?

Best for what?

I'd start with
?princomp
and if that doesn't meet your needs go looking farther.
www.rseek.org is good for finding R functions for particular purposes.

But if you're starting with the correlation matrix rather than the raw
data, you might need to do the eigenanalysis yourself rather than
relying on an existing function that assumes raw data.

Sarah

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