R help - Oct 2011 - New column of data filled with the larger value from 2 columns

Hi,
I'm sure there is a pretty simple answer to this but I have had my head
buried in the R book and on help pages for a while now and I've not made any
progress.

In simple terms:
I have 2 columns of data, column A and column B. I want to create a new
column (C) and fill it with the largest value from of A or B on each row.


So I want C to contain A if B>A
and C to contain B if A=>B


Like I said I have tried to look for an answer and I'm sure there is one (or
many) out there but I am looking in the wrong places or for the wrong terms
so I would really appreciate this help! 


Thanks,
Rob.

(I promise that once I have mastered R- hopefully in the near future- I will
make up for my sins of asking a basic Q by answering many on here!)

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robgriffin247 <robgriffin247 <at> hotmail.com> writes:
> 
> Hi,
> I'm sure there is a pretty simple answer to this but I have had my head
> buried in the R book and on help pages for a while now and I've not
made any
> progress.
> 
> In simple terms:
> I have 2 columns of data, column A and column B. I want to create a new
> column (C) and fill it with the largest value from of A or B on each row.
> 
  sounds like you want data$C <- pmax(data$A,data$B)
(or data <- transform(C,pmax(A,B)))

data$C <- pmax(data$A,data$B)

 worked perfectly thank you very much

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