avoid copying

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/coin@833 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
tweak

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/coin@834 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
use .int version of pmin/pmax

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/coin@835 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
use seq_along

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/coin@836 edb9625f-4e0d-4859-8d74-9fd3b1da38cb