[R] if else elseif for data frames

[jim holtman]

You might look at the 'recode' that is part of the 'car' package.  You
can also setup a dataframe with two columns; one with the current
value and one with the new value you want, then you can use 'merge' or
'match' to create your new column.  If you have provided some sample
data, I could have provided examples, but now left as an exercise for
the reader.

On Sun, Aug 12, 2012 at 9:07 PM, Sachinthaka Abeywardana
<sachin.abeywardana at gmail.com> wrote:
> The thing is I have about 10 cases. I saw the ifelse statement but was
> wondering if there was a cleaner method of doing it. The coding will get
> really messy when I write all 10 cases.
>
> Cheers,
> Sachin
>
> On Mon, Aug 13, 2012 at 11:04 AM, arun <smartpink111 at yahoo.com> wrote:
>
>> Hi,
>> Try this:
>> dat1<-data.frame(col1=c(rep("high",3),rep("Neutral",3),rep("low",4)))
>>
>>  dat1$col2<-ifelse(dat1$col1=="high",dat1$col2<-"H",ifelse(dat1$col1=="Neutral",dat1$col2<-"N","L"))
>> dat1
>>       col1 col2
>> 1     high    H
>> 2     high    H
>> 3     high    H
>> 4  Neutral    N
>> 5  Neutral    N
>> 6  Neutral    N
>> 7      low    L
>> 8      low    L
>> 9      low    L
>> 10     low    L
>>
>> A.K.
>>
>>
>>
>>
>> ----- Original Message -----
>> From: Sachinthaka Abeywardana <sachin.abeywardana at gmail.com>
>> To: r-help at r-project.org
>> Cc:
>> Sent: Sunday, August 12, 2012 8:43 PM
>> Subject: [R] if else elseif for data frames
>>
>> Hi all,
>>
>> It seems like I cannot use normal 'if' for data frames. What would be the
>> best way to do the following.
>>
>> if data$col1='high'
>>     data$col2='H'
>> else if data$col1='Neutral'
>>     data$col2='N'
>> else if data$col='low'
>>    data$col2='L'
>> else
>>    #chuch a warning?
>>
>>
>> Note that col2 was not an existing column and was newly assigned for this
>> task.
>>
>> Thanks,
>> Sachin
>>
>>     [[alternative HTML version deleted]]
>>
>> ______________________________________________
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>> 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.
>>
>>
>
>         [[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.



-- 
Jim Holtman
Data Munger Guru

What is the problem that you are trying to solve?
Tell me what you want to do, not how you want to do it.