An alternative approach would be to store 0 x 0 matrices instead of NULLs. This way every object in your list is a consistent type.
Hadley On Wed, Oct 15, 2008 at 5:23 AM, Muhammad Azam <[EMAIL PROTECTED]> wrote: > Dear friends > There is a list of arrays comprising different no of rows and columns even > sometimes NULL, such as [[2]] given below. How can we ignore [[2]] or others > like this in the complete list. Any help in this regard is needed. Thanks > > [[1]] > [,1] [,2] > [1,] 3 1 > [2,] 3 1 > [3,] 3 1 > > [[2]] > NULL > > [[3]] > [,1] [,2] [,3] [,4] [,5] [,6] [,7] > [1,] 3 1 0 0 0 0 0 > [2,] 3 1 0 0 0 0 0 > [3,] 3 1 0 0 0 0 0 > [4,] 3 1 3 1 3 2 1 > [5,] 3 1 3 1 3 2 1 > [6,] 3 1 3 1 3 2 0 > > [[4]] > [,1] [,2] [,3] [,4] > [1,] 3 0 0 0 > [2,] 3 1 3 3 > [3,] 3 1 3 3 > [4,] 3 1 3 0 > > OR > x1=c(1,2,3); x2=c(1,2,3,4,6); x3=c(); x=list(x1,x2,x3) > > M.Azam > > > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > -- http://had.co.nz/ ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.