hie 
   i'm tryimg to generate two survival data using the following code  (I know its ugly ) but it seems to repeat  two of the variables  can any one tell me whats the porblem.
  
      n=20
      n1=n/2
      n2=n/4
      a11=1 ;a12=1.4 ;a21=16 ;a22=a12 * a21
      t1<-array(1,c(n1))                                             
       t2<-array(2,c(n1))
      treatgrp=matrix(c(t1,t2))                                    
      st11<-array(1,c(n2))
       st12<-array(2,c(n2))
       st21<-array(1,c(n2))
       st22<-array(2,c(n2))
      strata=matrix(c(st11,st12,st21,st22))                 
      time11=array(rweibull(n2,a11,1))
      time12=array(rweibull(n2,a12,1))
      time21=array(rweibull(n2,a21,1))
      time22=array(rweibull(n2,a22,1))
      time=matrix(c(time11, time12, time21, time22))  
      censorTime=runif(n,0,1)
      m=cbind(treatgrp,strata,time,censorTime)                 . 
      colnames(m)=c(“treat”,”strata”,”time”,”censorTime”)
      
act.surv.time<-pmin(m[,"time"],m[,"censorTime"])
  
m<-cbind(m,act.surv.time)
      m<-cbind(m,0)
         m[m[,3]>m[,4],6]<-1
        colnames(m)[6]<-"censoring"
      m
    act.surv.time is repeated at the end of the data frame.
  
  thanks
  
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