Hi R users: How can I built a direct sum function of matrices in R? I mean A(mxn), B(pxq), C(rxs),... X<-ds(A,B,C,...) X = [ A, 0, 0 0, B, 0 0, 0, C] ((m+p+r+...) x (n+q+s+...)) Thank you for your help. Kenneth -- Using Opera's revolutionary e-mail client: http://www.opera.com/m2/