Re: [R] Find max of a row in data frame (like Excel)

From: Anh Tran <popophobia_at_gmail.com>
Date: Wed, 25 Jun 2008 14:51:30 -0700

Thanks all. I got the result I wanted. I appreciate all the pointer. I never fully understand the apply function, as well as the lapply. And this occasion is one of those where these functions comes in to play.

On Wed, Jun 25, 2008 at 2:10 PM, Kenn Konstabel <lebatsnok_at_gmail.com> wrote:

> apply max to columns f1...f4 and assign it to rs$f:
>
> rs$f <- apply(rs[,paste("f",1:4,sep="")],1,max)
>
> or
>
> rs$f <- apply(rs[,2:5],1,max)
>
>
>
> On Wed, Jun 25, 2008 at 1:41 AM, Anh Tran <popophobia_at_gmail.com> wrote:
>
>> Hi,
>> Here's the data we have:
>>
>> > rs[1:5,]
>> probe_id f1 f2 f3 f4 M A f
>> 1 A_68_P20002076 2 58 0 0 1.51778114 6.344453 59
>> 2 A_68_P20002775 22 8 15 0 0.43419304 5.488819 59
>> 3 A_68_P20005791 43 3 0 0 0.05698666 9.830594 59
>> 4 A_68_P20005805 11 34 0 0 1.71076835 6.624038 59
>> 5 A_68_P20006729 16 44 0 0 0.85498261 6.044229 59
>>
>> I want rs$f be the max of f1, f2, f3, f4 like a function in excel
>> (=max(f1,
>> f2, f3, f4)).
>>
>> How should we do it in R? I'm not familiar with programing with list. So
>> please be patient
>> Thanks
>> --
>> Regards,
>> Anh Tran
>>
>> [[alternative HTML version deleted]]
>>
>> ______________________________________________
>> R-help_at_r-project.org 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.
>>
>
>

-- 
Regards,
Anh Tran

	[[alternative HTML version deleted]]

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Received on Wed 25 Jun 2008 - 21:58:27 GMT

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