Hi, Try this: dat1$Percent<-unlist(tapply(dat1$Count,list(dat1$Trip_id,dat1$CommonName),function(x) x/sum(x))) head(dat1) #? Trip_id?? Vessel?? CommonName Length Count??? Percent #1???? 230 Sunlight ShadAmerican???? 19???? 1 0.01408451 #2???? 230 Sunlight ShadAmerican???? 20???? 1 0.01408451 #3???? 230 Sunlight ShadAmerican???? 21???? 1 0.02816901 #4???? 230 Sunlight ShadAmerican???? 23???? 1 0.05633803 #5???? 230 Sunlight ShadAmerican???? 26???? 1 0.22535211 #6???? 230 Sunlight ShadAmerican???? 27???? 1 0.30985915 I also have a doubt from your first email. ?"I am trying to use the aggregate function to calculate the percent at length for each Trip_id and CommonName. " So, I am thinking you need the percentage of "length".? If that is the case, res1<-with(dat1,aggregate(Count,by=list(Trip_id=Trip_id,CommonName=CommonName),function(x) length(x))) library(plyr) res1$Percent<-ddply(res1,.(Trip_id),summarize,x/sum(x))[,2] ?res1 #? Trip_id????? CommonName? x Percent #1???? 230???????? Alewife 11??? 0.44 #2???? 230 HerringBlueback? 4??? 0.16 #3???? 230??? ShadAmerican 10??? 0.40 #4???? 231??? ShadAmerican? 5??? 1.00 ?A.K.
From: Sally A Roman <sroman at umassd.edu>
To: arun <smartpink111 at yahoo.com>
Sent: Thursday, October 25, 2012 12:44 PM
Subject: Re: [R] trying ti use a function in aggregate
To: arun <smartpink111 at yahoo.com>
Sent: Thursday, October 25, 2012 12:44 PM
Subject: Re: [R] trying ti use a function in aggregate
Thank you for your help.? Your code does what I need it to, but the output that I need is Trip_id, Vessel, CommonName, Length, Percent.? When I run your functions there is no length output.? Do you have any suggestions on how to get the Length variable into the output? Thanks again- Sally ________________________________ From: "arun" <smartpink111 at yahoo.com> To: "Sally_roman" <sroman at umassd.edu> Cc: "R help" <r-help at r-project.org> Sent: Thursday, October 25, 2012 12:04:23 PM Subject: Re: [R] trying ti use a function in aggregate Hi, May be this helps: dat1<-read.table(text=" ?Trip_id????????? Vessel????? CommonName Length Count 1????? 230??????? Sunlight??? ShadAmerican??? 19??? 1 2????? 230??????? Sunlight??? ShadAmerican??? 20??? 1 3????? 230??????? Sunlight??? ShadAmerican??? 21??? 1 4????? 230??????? Sunlight??? ShadAmerican??? 23??? 1 5????? 230??????? Sunlight??? ShadAmerican??? 26??? 1 6????? 230??????? Sunlight??? ShadAmerican??? 27??? 1 7????? 230??????? Sunlight??? ShadAmerican??? 30??? 2 8????? 230??????? Sunlight??? ShadAmerican??? 33??? 1 9????? 230??????? Sunlight??? ShadAmerican??? 34??? 1 10??? 230??????? Sunlight??? ShadAmerican??? 37??? 1 11??? 230??????? Sunlight HerringBlueback??? 20??? 1 12??? 230??????? Sunlight HerringBlueback??? 21??? 2 13??? 230??????? Sunlight HerringBlueback??? 22??? 5 14??? 230??????? Sunlight HerringBlueback??? 26??? 1 15??? 230??????? Sunlight????????? Alewife??? 17??? 1 16??? 230??????? Sunlight????????? Alewife??? 18??? 1 17??? 230??????? Sunlight????????? Alewife??? 20??? 2 18??? 230??????? Sunlight????????? Alewife??? 21??? 4 19??? 230??????? Sunlight????????? Alewife??? 22??? 16 20??? 230??????? Sunlight????????? Alewife??? 23??? 22 21??? 230??????? Sunlight????????? Alewife??? 24??? 16 22??? 230??????? Sunlight????????? Alewife??? 25??? 4 23??? 230??????? Sunlight????????? Alewife??? 26??? 1 24??? 230??????? Sunlight????????? Alewife??? 27??? 2 25??? 230??????? Sunlight????????? Alewife??? 28??? 2 26??? 231 Western_Venture??? ShadAmerican??? 23??? 1 27??? 231 Western_Venture??? ShadAmerican??? 24??? 1 28??? 231 Western_Venture??? ShadAmerican??? 25??? 1 29??? 231 Western_Venture??? ShadAmerican??? 28??? 2 30??? 231 Western_Venture??? ShadAmerican??? 29??? 2 ",sep="",header=TRUE,stringsAsFactors=FALSE) with(dat1,aggregate(Count,by=list(Trip_id=Trip_id,Species=CommonName),function(x) x/sum(x))) ? Trip_id???????? Species 1???? 230???????? Alewife 2???? 230 HerringBlueback 3???? 230??? ShadAmerican 4???? 231??? ShadAmerican ?????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????? x #1 0.01408451, 0.01408451, 0.02816901, 0.05633803, 0.22535211, 0.30985915, 0.22535211, 0.05633803, 0.01408451, 0.02816901, 0.02816901 #2???????????????????????????????????????????????????????????????????????????????????????? 0.1111111, 0.2222222, 0.5555556, 0.1111111 #3???????????? 0.09090909, 0.09090909, 0.09090909, 0.09090909, 0.09090909, 0.09090909, 0.18181818, 0.09090909, 0.09090909, 0.09090909 #4????????????????????????????????????????????????????????????????????????????? 0.1428571, 0.1428571, 0.1428571, 0.2857143, 0.2857143 #or library(plyr) res<-ddply(dat1,.(Trip_id=Trip_id,Vessel=Vessel,CommonName=CommonName), summarize, Count/sum(Count)) colnames(res)[4]<-"value" head(res) #? Trip_id?? Vessel CommonName????? value #1???? 230 Sunlight??? Alewife 0.01408451 #2???? 230 Sunlight??? Alewife 0.01408451 #3???? 230 Sunlight??? Alewife 0.02816901 #4???? 230 Sunlight??? Alewife 0.05633803 #5???? 230 Sunlight??? Alewife 0.22535211 #6???? 230 Sunlight??? Alewife 0.30985915 A.K. ----- Original Message ----- From: Sally_roman <sroman at umassd.edu> To: r-help at r-project.org Cc: Sent: Thursday, October 25, 2012 10:19 AM Subject: [R] trying ti use a function in aggregate Hi -I am using R v 2.13.0.? I am trying to use the aggregate function to calculate the percent at length for each Trip_id and CommonName.? Here is a small subset of the data.? ? ?Trip_id? ? ? ? ? Vessel? ? ? ?CommonName Length Count 1? ? ? 230? ? ? ? Sunlight? ? Shad,American? ? ?19? ? ?1 2? ? ? 230? ? ? ? Sunlight? ? Shad,American? ? ?20? ? ?1 3? ? ? 230? ? ? ? Sunlight? ? Shad,American? ? ?21? ? ?1 4? ? ? 230? ? ? ? Sunlight? ? Shad,American? ? ?23? ? ?1 5? ? ? 230? ? ? ? Sunlight? ? Shad,American? ? ?26? ? ?1 6? ? ? 230? ? ? ? Sunlight? ? Shad,American? ? ?27? ? ?1 7? ? ? 230? ? ? ? Sunlight? ? Shad,American? ? ?30? ? ?2 8? ? ? 230? ? ? ? Sunlight? ? Shad,American? ? ?33? ? ?1 9? ? ? 230? ? ? ? Sunlight? ? Shad,American? ? ?34? ? ?1 10? ? ?230? ? ? ? Sunlight? ? Shad,American? ? ?37? ? ?1 11? ? ?230? ? ? ? Sunlight Herring,Blueback? ? ?20? ? ?1 12? ? ?230? ? ? ? Sunlight Herring,Blueback? ? ?21? ? ?2 13? ? ?230? ? ? ? Sunlight Herring,Blueback? ? ?22? ? ?5 14? ? ?230? ? ? ? Sunlight Herring,Blueback? ? ?26? ? ?1 15? ? ?230? ? ? ? Sunlight? ? ? ? ? Alewife? ? ?17? ? ?1 16? ? ?230? ? ? ? Sunlight? ? ? ? ? Alewife? ? ?18? ? ?1 17? ? ?230? ? ? ? Sunlight? ? ? ? ? Alewife? ? ?20? ? ?2 18? ? ?230? ? ? ? Sunlight? ? ? ? ? Alewife? ? ?21? ? ?4 19? ? ?230? ? ? ? Sunlight? ? ? ? ? Alewife? ? ?22? ? 16 20? ? ?230? ? ? ? Sunlight? ? ? ? ? Alewife? ? ?23? ? 22 21? ? ?230? ? ? ? Sunlight? ? ? ? ? Alewife? ? ?24? ? 16 22? ? ?230? ? ? ? Sunlight? ? ? ? ? Alewife? ? ?25? ? ?4 23? ? ?230? ? ? ? Sunlight? ? ? ? ? Alewife? ? ?26? ? ?1 24? ? ?230? ? ? ? Sunlight? ? ? ? ? Alewife? ? ?27? ? ?2 25? ? ?230? ? ? ? Sunlight? ? ? ? ? Alewife? ? ?28? ? ?2 26? ? ?231 Western Venture? ? Shad,American? ? ?23? ? ?1 27? ? ?231 Western Venture? ? Shad,American? ? ?24? ? ?1 28? ? ?231 Western Venture? ? Shad,American? ? ?25? ? ?1 29? ? ?231 Western Venture? ? Shad,American? ? ?28? ? ?2 30? ? ?231 Western Venture? ? Shad,American? ? ?29? ? ?2 My code is: myfun<-function (x) x/sum(x) b<-with(data,aggregate(x=list(Percent=Count),by=list(Trip_id=Trip_id,Length=Length,Species=CommonName), FUN="myfun")) My issue is that the percent is not be calculated by Trip_id and CommonName. The result is that each row has a percent of 1 indicating that myfun is not dividing by the sum of counts with a Trip_id/CommonName group.? Any help would be appreciated. Thank you -- View this message in context: http://r.789695.n4.nabble.com/trying-ti-use-a-function-in-aggregate-tp4647414.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.