[R] creating a new column

[Vladimir Eremeev]

To create 6th column in the matrix m, you should use the cbind function.
To calculate the vector of pairwise min or max values, you should use the
pmin and pmax functions:

act.surv.time<-pmin(m[,"censoringTime"],m[,"survivalTime"])
m<-cbind(m,act.surv.time)


raymond chiruka wrote:
> 
> hie l would like to create a 6th column "actual surv time" from the
> following data 
>   
>   the condition being
>   if  censoringTime>survivaltime then actual survtime =survival time
>   else actual survtime =censoring time
>   
>   the code l used to create the data is
>   
>        s=2
>        while(s!=0){ n=20
>          m<-matrix(nrow=n,ncol=4)
>         
> colnames(m)=c("treatmentgrp","strata","censoringTime","survivalTime")
>         for(i in 1:20) 
> m[i,]<-c(sample(c(1,2),1,replace=TRUE),sample(c(1,2),1,replace=TRUE),rexp(1,.007),rexp(1,.002))
>         m<-cbind(m,0)
>          m[m[,3]>m[,4],5]<-1
>          colnames(m)[5]<-"censoring"
>       print(m)
>        s=s-1
>           treatmentgrp strata censoringTime survivalTime censoring
>    [1,]             1      1       1.012159    1137.80922         0
>    [2,]             2      2      32.971439     247.21786         0
>    [3,]             2      1      85.758253     797.04949         0
>    [4,]             1      1      16.999171      78.92309         0
>    [5,]             2      1     272.909896     298.21483         0
>    [6,]             1      2     138.230629     935.96765         0
>    [7,]             2      2      91.529859     141.08405         0
>   
>   
>   l keep getting an error message when i try to  create the 6th column
>   
> ---------------------------------
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> 

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