Hi Anindya,
If you have multiple tables and it is in a folder, you can use: list.files() #I had three files in the working directory #[1] "test1.txt" "test2.txt" "test3.txt" library(data.table) dt1<-rbindlist(lapply(list.files(),function(x) read.table(x,header=FALSE,sep=""))) dt1 # V1 V2 #1: 1 10 #test1.txt #2: 3 5 #3: 0 0 #4: 2 10 #test2.txt #5: 0 0 #6: 3 5 #7: 4 10 #test3.txt #8: 0 0 #9: 3 5 dt2<-subset(dt1[,sum(V2),by=V1],V1!=0) setnames(dt2,2,"V2") dt2 # V1 V2 #1: 1 10 #2: 3 15 #3: 2 10 #4: 4 10 #or dat1<- do.call(rbind,lapply(list.files(),function(x) read.table(x,header=FALSE,sep=""))) res<-aggregate(V2~V1,data=dat1,FUN=sum) res1<- res[res[,1]!=0,] res1 # V1 V2 #2 1 10 #3 2 10 #4 3 15 #5 4 10 Hope this helps. A.K. ________________________________ From: Anindya Sankar Dey <anindy...@gmail.com> To: arun <smartpink...@yahoo.com> Cc: R help <r-help@r-project.org> Sent: Friday, August 23, 2013 9:55 AM Subject: Re: [R] Combining two tables without going through lot of ifelse statement Hi All, Arun's solution is working. Now can someone help me in just an expansion. If we have multiple table like this, adding them in rbind is working, but if I want a generic function where we do not know how many tables will be created can that also be avoided from using loops. On Fri, Aug 23, 2013 at 7:15 PM, arun <smartpink...@yahoo.com> wrote: > >In the case of ?data.table() > >dt1<-data.table(rbind(as.matrix(dat1),as.matrix(dat2))) ## converted the >data.frame to matrix to mimic the situation > > dt2<- subset(dt1[,sum(V2),by=V1],V1!=0) > > setnames(dt2,2,"V2") > dt2 ># V1 V2 >#1: 1 10 >#2: 3 10 >#3: 2 10 > > >#or > > >res<-with(as.data.frame(rbind(as.matrix(dat1),as.matrix(dat2))),aggregate(V2~V1,FUN=sum)) > res1<- res[res[,1]!=0,] > > res1 ># V1 V2 >#2 1 10 >#3 2 10 >#4 3 10 >A.K. >________________________________ > >From: Anindya Sankar Dey <anindy...@gmail.com> >To: arun <smartpink...@yahoo.com> >Sent: Friday, August 23, 2013 9:40 AM > >Subject: Re: [R] Combining two tables without going through lot of ifelse >statement > > > >Mine is matrices, will this work on matrices as well? > >Thank for your help > > > >On Fri, Aug 23, 2013 at 7:02 PM, arun <smartpink...@yahoo.com> wrote: > >However it is not clear when you mention these are tables. There is ?table() >and ?data.frame and the structure will be different in each case. Here, I >assumed that your table is data.frame.. >> >> >> >> >>----- Original Message ----- >>From: arun <smartpink...@yahoo.com> >>To: Anindya Sankar Dey <anindy...@gmail.com> >>Cc: R help <r-help@r-project.org> >>Sent: Friday, August 23, 2013 9:30 AM >>Subject: Re: [R] Combining two tables without going through lot of ifelse >> statement >> >>Hi, >>Try: >> >>dat1<- read.table(text=" >>1 10 >>3 5 >>0 0 >>",sep="",header=FALSE) >>dat2<- read.table(text=" >>2 10 >>0 0 >>3 5 >>",sep="",header=FALSE) >>res<-with(rbind(dat1,dat2),aggregate(V2~V1,FUN=sum)) >>res1<-res[res[,1]!=0,] >> res1 >># V1 V2 >>#2 1 10 >>#3 2 10 >>#4 3 10 >> >>#or >>library(data.table) >>dt1<- data.table(rbind(dat1,dat2)) >> dt2<-subset(dt1[,sum(V2),by=V1],V1!=0) >> setnames(dt2,2,"V2") >> dt2 >># V1 V2 >>#1: 1 10 >>#2: 3 10 >>#3: 2 10 >> >>A.K. >> >>----- Original Message ----- >>From: Anindya Sankar Dey <anindy...@gmail.com> >>To: r-help <r-help@r-project.org> >>Cc: >>Sent: Friday, August 23, 2013 8:59 AM >>Subject: [R] Combining two tables without going through lot of ifelse >>statement >> >>HI All, >> >>Suppose I have two table like below >> >>Table 1: >> >>1 10 >>3 5 >>0 0 >> >>Table 2: >> >>2 10 >>0 0 >>3 5 >> >> >>I need to create a new table like below >> >>Table 3: >> >>1 10 >>2 10 >>3 10 >> >>The row may interchange in table 3, but is there any way to do this instead >>of writing lot of if-else and loops? >> >>Thanks in advance. >> >>-- >>Anindya Sankar Dey >> >> [[alternative HTML version deleted]] >> >>______________________________________________ >>R-help@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. >> >> > > >-- >Anindya Sankar Dey > -- Anindya Sankar Dey ______________________________________________ R-help@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.
