Hello, Where is the problem in this programming. I want two way matrix, but it gives problem. The program is given below: rep = 2 genes = 5 pred = c() iter = array (dim = c(rep, pred)) pred array(dim = c(1, genes)) m = c() l = 1 w = 1 for(m in 1:rep) { t = time data c = cens tab = cbind(t, c) # Resampling Time and Censoring cc sample(c, replace = TRUE) # Bootstrap WR Censoring Data tt sample(t, replace = TRUE) # Bootstrap WR Time Data xx Surv(tt, cc) # Survival Times with Censored P = predic[,1:5] # First 5 Rows of predic n = 310 # Every Row has 310 values ma matrix(P, n) # P cross n, matrix boot <- sample(seq(n), replace=TRUE) # Bootstrap WR in seq(n) genes5 = ma[boot, ] # 5 genes Bootstrap Matrix for(p in 1: genes){ i = c() for(i in w:l) { z = genes5[,w: l] y = coxph(xx ~ z) } Pval = summary(y) $ coeff[, 5] if( any(Pval <= 0.01) ) sign <- 1 else sign <- 0 pred[1, p] = sign[1] } iter [m, 1:5] = pred[1: 5] } Thanks in advance. Regards Fazli Raziq [[alternative HTML version deleted]]