[R] More elegant way of stacking the data

[Dimitri Liakhovitski]

Thanks a lot, guys!

On Tue, Nov 25, 2014 at 9:42 AM, Lee, Chel Hee <chl948 at mail.usask.ca> wrote:
> If you do not want to use the loop, a function called 'reshape' may be
> useful:
>
>> df <- data.frame(a=1:5,b=letters[1:5],c1=1:5,c2=2:6,c3=3:7,c4=4:8)
>> out2 <- reshape(data=df, direction="long", varying=list(3:6),
>> times=paste("c",1:4,sep=""))
>> out2
>      a b time c1 id
> 1.c1 1 a   c1  1  1
> 2.c1 2 b   c1  2  2
> 3.c1 3 c   c1  3  3
> 4.c1 4 d   c1  4  4
> 5.c1 5 e   c1  5  5
> 1.c2 1 a   c2  2  1
> 2.c2 2 b   c2  3  2
> 3.c2 3 c   c2  4  3
> 4.c2 4 d   c2  5  4
> 5.c2 5 e   c2  6  5
> 1.c3 1 a   c3  3  1
> 2.c3 2 b   c3  4  2
> 3.c3 3 c   c3  5  3
> 4.c3 4 d   c3  6  4
> 5.c3 5 e   c3  7  5
> 1.c4 1 a   c4  4  1
> 2.c4 2 b   c4  5  2
> 3.c4 3 c   c4  6  3
> 4.c4 4 d   c4  7  4
> 5.c4 5 e   c4  8  5
>
> I hope this helps.
>
> Chel Hee Lee
>
>
> On 11/24/2014 5:12 PM, Dimitri Liakhovitski wrote:
>>
>> I have the data frame 'df' and my desired solution 'out'.
>> I am sure there is a more elegant R-way to do it - without a loop.
>>
>> df = data.frame(a=1:5,b=letters[1:5],c1=1:5,c2=2:6,c3=3:7,c4=4:8)
>> mylist=NULL
>> for(i in 1:4){
>>    myname<-paste("c",i,sep="")
>>    mylist[[i]]<-df[c("a","b",myname)]
>>    names(mylist[[i]])<-c("a","b","c")
>> }
>> out<-do.call(rbind,mylist)
>> out
>>
>> Thank you!
>>
>



-- 
Dimitri Liakhovitski