[R] creating a new column

[Schmitt, Corinna]

Hallo,

I just now a solution for da data frame. I'm not sure if this is what you want. Just try if it helps. Here an example of my code where I added a column:

df <- rbind( c("fred","mary",4),c("fred","mary",7),
             c("fred","mary",9),c("barney","liz",3),
             c("barney","liz",5))
df <- data.frame(df)
colnames(df) <- c("father","mother","child.age")

# adding column
df <- data.frame(df,"weddingdate"=c("Dec 12th, 1980","Dec 12th, 1980",
                                    "Dec 12th, 1980","Apr 9th, 2003",  
                                    "Apr 9th, 2003"))
df    
  
The R-Gui Result:
  father mother child.age    weddingdate
1   fred   mary         4 Dec 12th, 1980
2   fred   mary         7 Dec 12th, 1980
3   fred   mary         9 Dec 12th, 1980
4 barney    liz         3  Apr 9th, 2003
5 barney    liz         5  Apr 9th, 2003

Caution: the number of entries in adding column must correspond to the number of rows in your existing data frame df (here 5)

Try this soultion,
Corinna


-----Ursprüngliche Nachricht-----
Von: r-help-bounces at stat.math.ethz.ch [mailto:r-help-bounces at stat.math.ethz.ch] Im Auftrag von raymond chiruka
Gesendet: Montag, 7. Mai 2007 16:28
An: r
Betreff: [R] creating a new column

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
  
  
  
  
 	      
---------------------------------


	[[alternative HTML version deleted]]

______________________________________________
R-help at stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.