Hi. This is likely a trivial problem but have not found a solution. Imagine the following dataframe: Lat Lon x1 x2 x3 01 10 NA NA .1 01 11 NA .2 .3 01 12 .4 .5 .6 I want to generate another column that consist of the first value in each row from columns x1 to x3. That is NewColumn .1 .2 .4 Any input greatly appreciated, Thanks, Camilo Camilo Mora, Ph.D. Department of Geography, University of Hawaii
Hi Camilo, as you want to work on all rows, apply() is your friend. In the following, I use an anonymous function getting the first non-na value while looping over each row: dat <- read.table(text = " Lat Lon x1 x2 x3 01 10 NA NA .1 01 11 NA .2 .3 01 12 .4 .5 .6 ", header = TRUE) apply(dat[,-(1:2)], 1, function(x) x[!is.na(x)][1]) gives: [1] 0.1 0.2 0.4 Cheers, Henrik Camilo Mora schrieb:> Hi. > > This is likely a trivial problem but have not found a solution. Imagine > the following dataframe: > > Lat Lon x1 x2 x3 > 01 10 NA NA .1 > 01 11 NA .2 .3 > 01 12 .4 .5 .6 > > I want to generate another column that consist of the first value in > each row from columns x1 to x3. That is > > NewColumn > .1 > .2 > .4 > > Any input greatly appreciated, > > Thanks, > > Camilo > > > Camilo Mora, Ph.D. > Department of Geography, University of Hawaii >
Hi, Try this: dat1<-read.table(text=" Lat? Lon? x1? x2? x3 01??? 10? NA? NA? .1 01??? 11? NA? .2? .3 01??? 12? .4? .5? .6 ",sep="",header=TRUE) dat2<-dat1[,3:5] ?dat3<-data.frame(dat1,NewColumn=rev(unlist(lapply(dat2,function(x) x[!is.na(x)][1])))) row.names(dat3)<-1:nrow(dat3) ?dat3 ? Lat Lon? x1? x2? x3 NewColumn 1?? 1? 10? NA? NA 0.1?????? 0.1 2?? 1? 11? NA 0.2 0.3?????? 0.2 3?? 1? 12 0.4 0.5 0.6?????? 0.4 A.K. ----- Original Message ----- From: Camilo Mora <cmora at dal.ca> To: r-help at r-project.org Cc: Sent: Tuesday, July 24, 2012 2:48 AM Subject: [R] First value in a row Hi. This is likely a trivial problem but have not found a solution. Imagine the following dataframe: Lat? Lon? x1? x2? x3 01? ? 10? NA? NA? .1 01? ? 11? NA? .2? .3 01? ? 12? .4? .5? .6 I want to generate another column that consist of the first value in each row from columns x1 to x3. That is NewColumn .1 .2 .4 Any input greatly appreciated, Thanks, Camilo Camilo Mora, Ph.D. Department of Geography, University of Hawaii ______________________________________________ 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.
If there are a lot more rows than columns in your data.frame then looping
over columns is faster than looping over rows. Comparing
f2 <- function (dataFrame)
{
retval <- dataFrame[, 1]
for (col in dataFrame[-1]) {
na <- is.na(retval)
if (!any(na))
break
retval[na] <- col[na]
}
retval
}
to the looping over row version
f1 <- function (dataFrame) apply(dataFrame, 1, function(x) x[!is.na(x)][1])
for a 250,000 row by 3 coludata.frame, f1 takes 2.48 seconds and f1 0.02.
Bill Dunlap
Spotfire, TIBCO Software
wdunlap tibco.com
> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at
r-project.org] On
> Behalf Of Henrik Singmann
> Sent: Tuesday, July 24, 2012 1:40 AM
> To: r-help at stat.math.ethz.ch
> Subject: Re: [R] First value in a row
>
> Hi Camilo,
>
> as you want to work on all rows, apply() is your friend.
> In the following, I use an anonymous function getting the first non-na
> value while looping over each row:
>
> dat <- read.table(text = "
> Lat Lon x1 x2 x3
> 01 10 NA NA .1
> 01 11 NA .2 .3
> 01 12 .4 .5 .6
> ", header = TRUE)
>
> apply(dat[,-(1:2)], 1, function(x) x[!is.na(x)][1])
>
> gives:
> [1] 0.1 0.2 0.4
>
> Cheers,
> Henrik
>
> Camilo Mora schrieb:
> > Hi.
> >
> > This is likely a trivial problem but have not found a solution.
Imagine
> > the following dataframe:
> >
> > Lat Lon x1 x2 x3
> > 01 10 NA NA .1
> > 01 11 NA .2 .3
> > 01 12 .4 .5 .6
> >
> > I want to generate another column that consist of the first value in
> > each row from columns x1 to x3. That is
> >
> > NewColumn
> > .1
> > .2
> > .4
> >
> > Any input greatly appreciated,
> >
> > Thanks,
> >
> > Camilo
> >
> >
> > Camilo Mora, Ph.D.
> > Department of Geography, University of Hawaii
> >
>
> ______________________________________________
> 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.
Hi, I think it was due to a row with all the NAs.? I hope it happens rarely. In those cases, you can assign NAs from looking at the list. dat2<-data.frame(t(dat1[,3:5])) dat3<-lapply(dat2,function(x) tail(x[!is.na(x)],1)) ?dat3 $X1 [1] 0.6 $X2 [1] 0.3 $X3 [1] 0.1 $X4 numeric(0) ?dat3$X4<-NA dat4<-data.frame(dat1,NewColumn=unlist(dat3)) rownames(dat4)<-1:nrow(dat4) ?dat4 # Lat Lon? x1? x2? x3 NewColumn #1?? 1? 12 0.4 0.5 0.6?????? 0.6 #2?? 1? 12 0.2 0.3? NA?????? 0.3 #3?? 1? 11 0.1? NA? NA?????? 0.1 #4?? 1? 10? NA? NA? NA??????? NA ################################## #Another way elegant #or you can find the NA by using dat3<-lapply(dat2,function(x) tail(x[!is.na(x)],1))dat4<-ifelse(sapply(dat3,length)==0,NA,dat3) dat5<-data.frame(dat1,NewColumn=unlist(dat4)) rownames(dat5)<-1:nrow(dat5) dat5 ? Lat Lon? x1? x2? x3 NewColumn 1?? 1? 12 0.4 0.5 0.6?????? 0.6 2?? 1? 12 0.2 0.3? NA?????? 0.3 3?? 1? 11 0.1? NA? NA?????? 0.1 4?? 1? 10? NA? NA? NA??????? NA A.K. ----- Original Message ----- From: Camilo Mora <cmora at dal.ca> To: arun <smartpink111 at yahoo.com> Cc: Sent: Tuesday, July 24, 2012 11:30 PM Subject: Re: First value in a row Hi Arun, It works partially.... your script skip those rows full of NAs causing a different vector size, which then prevents merging the results to the original database. Any way to keep rows with all NAs? C Camilo Mora, Ph.D. Department of Geography, University of Hawaii Currently available in Colombia Phone:? Country code: 57 ? ? ? ? Provider code: 313 ? ? ? ? Phone 776 2282 ? ? ? ? From the USA or Canada you have to dial 011 57 313 776 2282 http://www.soc.hawaii.edu/mora/ Quoting arun <smartpink111 at yahoo.com>:> > > Hi Camilo, > > You can either use Henrik's or mine to find it, > ?unlist(apply(dat1[,-(1:2)],1,function(x) tail(x[!is.na(x)],1))) > ?x3? x2? x1 > 0.6 0.3 0.1 > > #or you can use my functiton > > dat3<-data.frame(NewColumn=c(unlist(lapply(dat2,function(x) tail(x[!is.na(x)],1))),NA)) > ?dat4<-data.frame(dat1,dat3) > ?rownames(dat4)<-1:nrow(dat4) > ?dat4 > #? Lat Lon? x1? x2? x3 NewColumn > #1?? 1? 12 0.4 0.5 0.6?????? 0.6 > #2?? 1? 12 0.2 0.3? NA?????? 0.3 > #3?? 1? 11 0.1? NA? NA?????? 0.1 > #4?? 1? 10? NA? NA? NA??????? NA > > A.K. > > > > > > > ----- Original Message ----- > From: Camilo Mora <cmora at dal.ca> > To: arun <smartpink111 at yahoo.com> > Cc: Henrik Singmann <henrik.singmann at psychologie.uni-freiburg.de>; R help <r-help at r-project.org> > Sent: Tuesday, July 24, 2012 10:56 PM > Subject: Re: First value in a row > > Hi Henrik and Arun, > > I now understand the script you provided. Very smart solution I think. I wonder, however, if there is an alternative way as to count the last number in a row?. > For instance, considering the following dataframe > > dat1<-read.table(text=" > Lat? Lon? x1? x2? x3 > 01? ? 12? .4? .5? .6 > 01? ? 12? .2? .3? NA > 01? ? 11? .1? NA? NA > 01? ? 10? NA? NA? NA > ",sep="",header=TRUE) > > the last value (from left to right) should be: > .6 > .3 > .1 > NA > > NAs are always consecutive once they appear. > > Thanks again, > > Camilo > > > Camilo Mora, Ph.D. > Department of Geography, University of Hawaii > Currently available in Colombia > Phone:?? Country code: 57 > ? ? ? ?? Provider code: 313 > ? ? ? ?? Phone 776 2282 > ? ? ? ?? From the USA or Canada you have to dial 011 57 313 776 2282 > http://www.soc.hawaii.edu/mora/ > > > > Quoting arun <smartpink111 at yahoo.com>: > >> Hi Henrik, >> >> Thanks for testing it to a different dataset.? I didn't test it at that time to multiple conditions.? Probably, apply is a better method. >> >> >> Anyway, you can still get the same result by doing this: >> >> dat1<-read.table(text=" >> Lat? Lon? x1? x2? x3 >> 01? ? 10? NA? NA? .1 >> 01? ? 11? .4? NA? .3 >> 01? ? 12? NA? .5? .6 >> ",sep="",header=TRUE) >> dat2<-data.frame(t(dat1[,3:5])) >> dat3<-data.frame(dat1,NewColumn=unlist(lapply(dat2,function(x) x[!is.na(x)][1]))) >> ?row.names(dat3)<-1:nrow(dat3) >> ?dat3 >> #? Lat Lon? x1? x2? x3 NewColumn >> #1?? 1? 10? NA? NA 0.1?????? 0.1 >> #2?? 1? 11 0.4? NA 0.3?????? 0.4 >> #3?? 1? 12? NA 0.5 0.6?????? 0.5 >> >> #Now, to a slightly different dataset >> dat1<-read.table(text=" >> Lat? Lon? x1? x2? x3 >> 01? ? 10? NA? NA? NA >> 01? ? 11? NA? NA? .3 >> 01? ? 12? NA? .6?? NA >> ",sep="",header=TRUE) >> ?dat2<-data.frame(t(dat1[,3:5])) >> ?dat3<-data.frame(dat1,NewColumn=unlist(lapply(dat2,function(x) x[!is.na(x)][1]))) >> ? row.names(dat3)<-1:nrow(dat3) >> ? dat3 >> ? #Lat Lon x1? x2? x3 NewColumn >> #1?? 1? 10 NA? NA? NA??????? NA >> #2?? 1? 11 NA? NA 0.3?????? 0.3 >> #3?? 1? 12 NA 0.6? NA?????? 0.6 >> >> >> I hope this works well. >> >> >> A.K. >> >> >> >> >> ----- Original Message ----- >> From: Henrik Singmann <henrik.singmann at psychologie.uni-freiburg.de> >> To: arun <smartpink111 at yahoo.com> >> Cc: Camilo Mora <cmora at dal.ca>; R help <r-help at r-project.org> >> Sent: Tuesday, July 24, 2012 10:18 AM >> Subject: Re: First value in a row >> >> Hi, >> >> As Arun's idea was also my first idea let me pinpoint the problem of this solution. >> It only works if the data in question (i.e., columns x1 to x3) follow the pattern of the example data insofar that the NAs form a triangle like structure. This is so because it loops over columns instead of rows and takes advantage of the triangle NA structure. >> >> For example, slightly changing the data leads to a result that does not follow the description of Camilo seem to want: >> >> dat1<-read.table(text=" >> Lat? Lon? x1? x2? x3 >> 01? ? 10? NA? NA? .1 >> 01? ? 11? .4? NA? .3 >> 01? ? 12? NA? .5? .6 >> ",sep="",header=TRUE) >> >> # correct answer from description would be .1, .4, .5 >> >> # arun's solution: >> data.frame(dat1,NewColumn=rev(unlist(lapply(dat1[,3:5],function(x) x[!is.na(x)][1])))) >> >> #? x3? x2? x1 >> # 0.1 0.5 0.4 >> >> # my solution: >> apply(dat1[,-(1:2)], 1, function(x) x[!is.na(x)][1]) >> >> # [1] 0.1 0.4 0.5 >> >> So the question is, what you want and how the data looks. >> >> Cheers, >> Henrik >> >> >> Am 24.07.2012 14:27, schrieb arun: >>> Hi, >>> >>> Try this: >>> >>> dat1<-read.table(text=" >>> Lat? Lon? x1? x2? x3 >>> 01? ? 10? NA? NA? .1 >>> 01? ? 11? NA? .2? .3 >>> 01? ? 12? .4? .5? .6 >>> ",sep="",header=TRUE) >>> >>> dat2<-dat1[,3:5] >>> ?? dat3<-data.frame(dat1,NewColumn=rev(unlist(lapply(dat2,function(x) x[!is.na(x)][1])))) >>> row.names(dat3)<-1:nrow(dat3) >>> ?? dat3 >>> ? ? Lat Lon? x1? x2? x3 NewColumn >>> 1?? 1? 10? NA? NA 0.1? ? ?? 0.1 >>> 2?? 1? 11? NA 0.2 0.3? ? ?? 0.2 >>> 3?? 1? 12 0.4 0.5 0.6? ? ?? 0.4 >>> >>> A.K. >>> >>> >>> >>> >>> ----- Original Message ----- >>> From: Camilo Mora <cmora at dal.ca> >>> To: r-help at r-project.org >>> Cc: >>> Sent: Tuesday, July 24, 2012 2:48 AM >>> Subject: [R] First value in a row >>> >>> Hi. >>> >>> This is likely a trivial problem but have not found a solution. Imagine the following dataframe: >>> >>> Lat?? Lon? x1?? x2? x3 >>> 01? ? 10?? NA?? NA? .1 >>> 01? ? 11?? NA?? .2? .3 >>> 01? ? 12?? .4?? .5? .6 >>> >>> I want to generate another column that consist of the first value in each row from columns x1 to x3. That is >>> >>> NewColumn >>> .1 >>> .2 >>> .4 >>> >>> Any input greatly appreciated, >>> >>> Thanks, >>> >>> Camilo >>> >>> >>> Camilo Mora, Ph.D. >>> Department of Geography, University of Hawaii >>> >>> ______________________________________________ >>> 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. >>> >>> >> >> -- >> Dipl. Psych. Henrik Singmann >> PhD Student >> Albert-Ludwigs-Universit?t Freiburg, Germany >> http://www.psychologie.uni-freiburg.de/Members/singmann >> >> >> > >
Hi Camilo, Glad it worked well.? You mentioned replacing zeros with 1s.? You can use the same function, replace NA by 1. dat4<-ifelse(sapply(dat3,length)==0,1,dat3) A.K. ----- Original Message ----- From: Camilo Mora <cmora at dal.ca> To: arun <smartpink111 at yahoo.com> Cc: Sent: Wednesday, July 25, 2012 1:15 AM Subject: Re: First value in a row Thanks Arun, Your funbction is the most promising. I am trying to replace Zeros with 1s and see it that works. I have this script within a loop so I can not replace by hand NAs C Camilo Mora, Ph.D. Department of Geography, University of Hawaii Currently available in Colombia Phone:? Country code: 57 ? ? ? ? Provider code: 313 ? ? ? ? Phone 776 2282 ? ? ? ? From the USA or Canada you have to dial 011 57 313 776 2282 http://www.soc.hawaii.edu/mora/ Quoting arun <smartpink111 at yahoo.com>:> Hi Camilo, > > I hope the second solution in my last email works for you. > A.K. > > > > ----- Original Message ----- > From: Camilo Mora <cmora at dal.ca> > To: arun <smartpink111 at yahoo.com> > Cc: > Sent: Tuesday, July 24, 2012 11:30 PM > Subject: Re: First value in a row > > Hi Arun, > > It works partially.... your script skip those rows full of NAs causing a different vector size, which then prevents merging the results to the original database. Any way to keep rows with all NAs? > > C > > > Camilo Mora, Ph.D. > Department of Geography, University of Hawaii > Currently available in Colombia > Phone:?? Country code: 57 > ? ? ? ?? Provider code: 313 > ? ? ? ?? Phone 776 2282 > ? ? ? ?? From the USA or Canada you have to dial 011 57 313 776 2282 > http://www.soc.hawaii.edu/mora/ > > > > Quoting arun <smartpink111 at yahoo.com>: > >> >> >> Hi Camilo, >> >> You can either use Henrik's or mine to find it, >> ?unlist(apply(dat1[,-(1:2)],1,function(x) tail(x[!is.na(x)],1))) >> ?x3? x2? x1 >> 0.6 0.3 0.1 >> >> #or you can use my functiton >> >> dat3<-data.frame(NewColumn=c(unlist(lapply(dat2,function(x) tail(x[!is.na(x)],1))),NA)) >> ?dat4<-data.frame(dat1,dat3) >> ?rownames(dat4)<-1:nrow(dat4) >> ?dat4 >> #? Lat Lon? x1? x2? x3 NewColumn >> #1?? 1? 12 0.4 0.5 0.6?????? 0.6 >> #2?? 1? 12 0.2 0.3? NA?????? 0.3 >> #3?? 1? 11 0.1? NA? NA?????? 0.1 >> #4?? 1? 10? NA? NA? NA??????? NA >> >> A.K. >> >> >> >> >> >> >> ----- Original Message ----- >> From: Camilo Mora <cmora at dal.ca> >> To: arun <smartpink111 at yahoo.com> >> Cc: Henrik Singmann <henrik.singmann at psychologie.uni-freiburg.de>; R help <r-help at r-project.org> >> Sent: Tuesday, July 24, 2012 10:56 PM >> Subject: Re: First value in a row >> >> Hi Henrik and Arun, >> >> I now understand the script you provided. Very smart solution I think. I wonder, however, if there is an alternative way as to count the last number in a row?. >> For instance, considering the following dataframe >> >> dat1<-read.table(text=" >> Lat? Lon? x1? x2? x3 >> 01? ? 12? .4? .5? .6 >> 01? ? 12? .2? .3? NA >> 01? ? 11? .1? NA? NA >> 01? ? 10? NA? NA? NA >> ",sep="",header=TRUE) >> >> the last value (from left to right) should be: >> .6 >> .3 >> .1 >> NA >> >> NAs are always consecutive once they appear. >> >> Thanks again, >> >> Camilo >> >> >> Camilo Mora, Ph.D. >> Department of Geography, University of Hawaii >> Currently available in Colombia >> Phone:?? Country code: 57 >> ? ? ? ?? Provider code: 313 >> ? ? ? ?? Phone 776 2282 >> ? ? ? ?? From the USA or Canada you have to dial 011 57 313 776 2282 >> http://www.soc.hawaii.edu/mora/ >> >> >> >> Quoting arun <smartpink111 at yahoo.com>: >> >>> Hi Henrik, >>> >>> Thanks for testing it to a different dataset.? I didn't test it at that time to multiple conditions.? Probably, apply is a better method. >>> >>> >>> Anyway, you can still get the same result by doing this: >>> >>> dat1<-read.table(text=" >>> Lat? Lon? x1? x2? x3 >>> 01? ? 10? NA? NA? .1 >>> 01? ? 11? .4? NA? .3 >>> 01? ? 12? NA? .5? .6 >>> ",sep="",header=TRUE) >>> dat2<-data.frame(t(dat1[,3:5])) >>> dat3<-data.frame(dat1,NewColumn=unlist(lapply(dat2,function(x) x[!is.na(x)][1]))) >>> ?row.names(dat3)<-1:nrow(dat3) >>> ?dat3 >>> #? Lat Lon? x1? x2? x3 NewColumn >>> #1?? 1? 10? NA? NA 0.1?????? 0.1 >>> #2?? 1? 11 0.4? NA 0.3?????? 0.4 >>> #3?? 1? 12? NA 0.5 0.6?????? 0.5 >>> >>> #Now, to a slightly different dataset >>> dat1<-read.table(text=" >>> Lat? Lon? x1? x2? x3 >>> 01? ? 10? NA? NA? NA >>> 01? ? 11? NA? NA? .3 >>> 01? ? 12? NA? .6?? NA >>> ",sep="",header=TRUE) >>> ?dat2<-data.frame(t(dat1[,3:5])) >>> ?dat3<-data.frame(dat1,NewColumn=unlist(lapply(dat2,function(x) x[!is.na(x)][1]))) >>> ? row.names(dat3)<-1:nrow(dat3) >>> ? dat3 >>> ? #Lat Lon x1? x2? x3 NewColumn >>> #1?? 1? 10 NA? NA? NA??????? NA >>> #2?? 1? 11 NA? NA 0.3?????? 0.3 >>> #3?? 1? 12 NA 0.6? NA?????? 0.6 >>> >>> >>> I hope this works well. >>> >>> >>> A.K. >>> >>> >>> >>> >>> ----- Original Message ----- >>> From: Henrik Singmann <henrik.singmann at psychologie.uni-freiburg.de> >>> To: arun <smartpink111 at yahoo.com> >>> Cc: Camilo Mora <cmora at dal.ca>; R help <r-help at r-project.org> >>> Sent: Tuesday, July 24, 2012 10:18 AM >>> Subject: Re: First value in a row >>> >>> Hi, >>> >>> As Arun's idea was also my first idea let me pinpoint the problem of this solution. >>> It only works if the data in question (i.e., columns x1 to x3) follow the pattern of the example data insofar that the NAs form a triangle like structure. This is so because it loops over columns instead of rows and takes advantage of the triangle NA structure. >>> >>> For example, slightly changing the data leads to a result that does not follow the description of Camilo seem to want: >>> >>> dat1<-read.table(text=" >>> Lat? Lon? x1? x2? x3 >>> 01? ? 10? NA? NA? .1 >>> 01? ? 11? .4? NA? .3 >>> 01? ? 12? NA? .5? .6 >>> ",sep="",header=TRUE) >>> >>> # correct answer from description would be .1, .4, .5 >>> >>> # arun's solution: >>> data.frame(dat1,NewColumn=rev(unlist(lapply(dat1[,3:5],function(x) x[!is.na(x)][1])))) >>> >>> #? x3? x2? x1 >>> # 0.1 0.5 0.4 >>> >>> # my solution: >>> apply(dat1[,-(1:2)], 1, function(x) x[!is.na(x)][1]) >>> >>> # [1] 0.1 0.4 0.5 >>> >>> So the question is, what you want and how the data looks. >>> >>> Cheers, >>> Henrik >>> >>> >>> Am 24.07.2012 14:27, schrieb arun: >>>> Hi, >>>> >>>> Try this: >>>> >>>> dat1<-read.table(text=" >>>> Lat? Lon? x1? x2? x3 >>>> 01? ? 10? NA? NA? .1 >>>> 01? ? 11? NA? .2? .3 >>>> 01? ? 12? .4? .5? .6 >>>> ",sep="",header=TRUE) >>>> >>>> dat2<-dat1[,3:5] >>>> ?? dat3<-data.frame(dat1,NewColumn=rev(unlist(lapply(dat2,function(x) x[!is.na(x)][1])))) >>>> row.names(dat3)<-1:nrow(dat3) >>>> ?? dat3 >>>> ? ? Lat Lon? x1? x2? x3 NewColumn >>>> 1?? 1? 10? NA? NA 0.1? ? ?? 0.1 >>>> 2?? 1? 11? NA 0.2 0.3? ? ?? 0.2 >>>> 3?? 1? 12 0.4 0.5 0.6? ? ?? 0.4 >>>> >>>> A.K. >>>> >>>> >>>> >>>> >>>> ----- Original Message ----- >>>> From: Camilo Mora <cmora at dal.ca> >>>> To: r-help at r-project.org >>>> Cc: >>>> Sent: Tuesday, July 24, 2012 2:48 AM >>>> Subject: [R] First value in a row >>>> >>>> Hi. >>>> >>>> This is likely a trivial problem but have not found a solution. Imagine the following dataframe: >>>> >>>> Lat?? Lon? x1?? x2? x3 >>>> 01? ? 10?? NA?? NA? .1 >>>> 01? ? 11?? NA?? .2? .3 >>>> 01? ? 12?? .4?? .5? .6 >>>> >>>> I want to generate another column that consist of the first value in each row from columns x1 to x3. That is >>>> >>>> NewColumn >>>> .1 >>>> .2 >>>> .4 >>>> >>>> Any input greatly appreciated, >>>> >>>> Thanks, >>>> >>>> Camilo >>>> >>>> >>>> Camilo Mora, Ph.D. >>>> Department of Geography, University of Hawaii >>>> >>>> ______________________________________________ >>>> 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. >>>> >>>> >>> >>> -- >>> Dipl. Psych. Henrik Singmann >>> PhD Student >>> Albert-Ludwigs-Universit?t Freiburg, Germany >>> http://www.psychologie.uni-freiburg.de/Members/singmann >>> >>> >>> >> >> > >