[R] how to get coefficient and scores of Principal component analysis in R?

[Sarah Goslee]

By coefficients do you mean loadings?

Anyway, if you read the help for princomp -- ?princomp -- will
get that, you'll see that it says, in part:

     ‘princomp’ returns a list with class ‘"princomp"’ containing the
     following components:

    sdev: the standard deviations of the principal components.

loadings: the matrix of variable loadings (i.e., a matrix whose columns
          contain the eigenvectors).  This is of class ‘"loadings"’:
          see ‘loadings’ for its ‘print’ method.

  scores: if ‘scores = TRUE’, the scores of the supplied data on the
          principal components.  These are non-null only if ‘x’ was
          supplied, and if ‘covmat’ was also supplied if it was a
          covariance list.  For the formula method, ‘napredict()’ is
          applied to handle the treatment of values omitted by the
          ‘na.action’.

So for instance,

myprincomp <- princomp(mydata)
myprincomp$scores # shows the scores

Sarah

On Fri, Jan 28, 2011 at 2:16 PM, Zunqiu Chen <chener at ohsu.edu> wrote:
> Dear All,
>
> It might be a simple question. But I could not find the answer from function “prcomp” or “princomp”. Does anyone know what are the codes to get coefficient and scores of Principal component analysis in R?
>
> Your reply will be appreciated!
>
> Best
> Zunqiu
>



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