[Gretl-users] A Matrix Question

Dear all, I have a matrix "r" (attached in the Gretl session file) and need to calculate the following values: R6 = r[6,1] + r[5,2] + r[4,3] + r[3,4] + r[2,5] + r[1,6] R7 = r[7,1] + r[6,2] + r[5,3] + r[4,4] + r[3,5] + r[2,6] . . . R12 = r[12,1] + r[11,2] + r[10,3] + r[9,4] + r[8,5] + r[7,6] After this I need to make a new matrix: [R6 R7 R8 ... R12]' I know how to do this "by hand", but I would like to perform this task using a script. Would you help me? Thanks in advance, Henrique C. de Andrade Doutorando em Economia Aplicada Universidade Federal do Rio Grande do Sul www.ufrgs.br/ppge