- correct error in plotCv

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/mpalars@138 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
- reduce example duration

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/mpalars@139 edb9625f-4e0d-4859-8d74-9fd3b1da38cb