Dear R Users, I have created a 1500 x 20000 data frame - DataSeq. Each of the 1500 rows represents a data sequence. I have another data frame iData that stores the information of these 1500 data sequences in the same order, for example, condition, gender, etc. If I use "subset" to select certain groups within iData according to some criteria that I have set, e.g. condition, gender Then how can I used the retrieved subset of iData to point to and retrieve corresponding rows in the DataSeq data.frame for manipulations and analysis? I hope some of you can give me some idea! Thank you very much!!! - John
Assuming that you get the list of indices into iData for the criteria, then you can use that to get the appropriate rows: indx <- which(iData >5) # or whatever your criteria is DataSeq[indx,, drop=FALSE] # gives you a subset matrix of just the rows you are interested in. On Thu, May 21, 2009 at 10:10 AM, tsunhin wong <thjwong@gmail.com> wrote:> Dear R Users, > > I have created a 1500 x 20000 data frame - DataSeq. Each of the 1500 > rows represents a data sequence. > I have another data frame iData that stores the information of these > 1500 data sequences in the same order, for example, condition, gender, > etc. > > If I use "subset" to select certain groups within iData according to > some criteria that I have set, e.g. condition, gender > Then how can I used the retrieved subset of iData to point to and > retrieve corresponding rows in the DataSeq data.frame for > manipulations and analysis? > > I hope some of you can give me some idea! > Thank you very much!!! > > - John > > ______________________________________________ > 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<http://www.r-project.org/posting-guide.html> > and provide commented, minimal, self-contained, reproducible code. >-- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem that you are trying to solve? [[alternative HTML version deleted]]
Dear Jim,
Thanks for your suggestion.
I have a follow-up question for fellow R Users that have followed this thread:
*I used to create two lists by some very flexible criteria to compare
from "iData" and pass the two lists to *ANOTHER FUNCTION* that further
decompose the two lists and do some case by case analysis:
comp.lst[[1]] <- subset(iData,(Session==1 & TrialList==2 &
BadTrial==0
& Correct==1 & Critical.BT>0))
comp.lst[[2]] <- subset(iData,(Session==2 & TrialList==2 &
BadTrial==0
& Correct==1 & Critical.BT>0))
*The function will then do some subject by subject processing:
tmplist <- comp.lst[[1]]
subject <- unique(tmplist$Subject)
Psubjmatrix <- NULL
for(j in 1:length(subj)) { ##divide the list and process per subject in the list
subjtriallist <- subset(tmplist,(Subject==subj[j])) ##divide
the list and process per subject in the list
print(paste("Start working on Subject
",subj[j],sep=""),quote=FALSE)
##The sub-divided list is passed to another function to
extract data from corresponding object
Ptrialmatrix <- SeekObject(subjtriallist,seconds,samplesize,sdmax);
##add rowmean to subject pupil matrix
Psubjmatrix <- cbind(Psubjmatrix, rowMeans(Ptrialmatrix,
na.rm=TRUE, dims=1))
}
*But now, I have a pre-processed the objects and cooked up a
1500x20000 matrix, and there is no need to get these objects one by
one for extraction, I may just do the following:
Ptrialmatrix <- PMasterMatrix[subjindex,,drop=FALSE]
*However, on passing the index to the function, I cannot further
sub-divide the list index by Subject.
I have been thinking of passing the criteria to within the function.
But... what smarter thing I can do to make it works?
- John
On Thu, May 21, 2009 at 10:33 AM, jim holtman <jholtman at gmail.com>
wrote:> Assuming that you get the list of indices into iData for the criteria, then
> you can use that to get the appropriate rows:
>
> indx <- which(iData >5)? # or whatever your criteria is
> DataSeq[indx,, drop=FALSE]? # gives you a subset matrix of just the rows
you
> are interested in.
>
> On Thu, May 21, 2009 at 10:10 AM, tsunhin wong <thjwong at gmail.com>
wrote:
>>
>> Dear R Users,
>>
>> I have created a 1500 x 20000 data frame - DataSeq. Each of the 1500
>> rows represents a data sequence.
>> I have another data frame iData that stores the information of these
>> 1500 data sequences in the same order, for example, condition, gender,
>> etc.
>>
>> If I use "subset" to select certain groups within iData
according to
>> some criteria that I have set, e.g. condition, gender
>> Then how can I used the retrieved subset of iData to point to and
>> retrieve corresponding rows in the DataSeq data.frame for
>> manipulations and analysis?
>>
>> I hope some of you can give me some idea!
>> Thank you very much!!!
>>
>> - John
>>
>> ______________________________________________
>> 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
> Cincinnati, OH
> +1 513 646 9390
>
> What is the problem that you are trying to solve?
>
Dear all, I found the answer: intersect() - John On Thu, May 21, 2009 at 7:32 PM, tsunhin wong <thjwong at gmail.com> wrote:> Dear Jim, > Thanks for your suggestion. > > I have a follow-up question for fellow R Users that have followed this thread: > > *I used to create two lists by some very flexible criteria to compare > from "iData" and pass the two lists to *ANOTHER FUNCTION* that further > decompose the two lists and do some case by case analysis: > > comp.lst[[1]] <- subset(iData,(Session==1 & TrialList==2 & BadTrial==0 > & Correct==1 & Critical.BT>0)) > comp.lst[[2]] <- subset(iData,(Session==2 & TrialList==2 & BadTrial==0 > & Correct==1 & Critical.BT>0)) > > *The function will then do some subject by subject processing: > > tmplist <- comp.lst[[1]] > subject <- unique(tmplist$Subject) > Psubjmatrix <- NULL > for(j in 1:length(subj)) { ##divide the list and process per subject in the list > ? ? ? ?subjtriallist <- subset(tmplist,(Subject==subj[j])) ##divide > the list and process per subject in the list > ? ? ? ?print(paste("Start working on Subject ",subj[j],sep=""),quote=FALSE) > ? ? ? ?##The sub-divided list is passed to another function to > extract data from corresponding object > ? ? ? ?Ptrialmatrix <- SeekObject(subjtriallist,seconds,samplesize,sdmax); > ? ? ? ?##add rowmean to subject pupil matrix > ? ? ? ?Psubjmatrix <- cbind(Psubjmatrix, rowMeans(Ptrialmatrix, > na.rm=TRUE, dims=1)) > } > > *But now, I have a pre-processed the objects and cooked up a > 1500x20000 matrix, and there is no need to get these objects one by > one for extraction, I may just do the following: > > Ptrialmatrix <- PMasterMatrix[subjindex,,drop=FALSE] > > *However, on passing the index to the function, I cannot further > sub-divide the list index by Subject. > > I have been thinking of passing the criteria to within the function. > But... what smarter thing I can do to make it works? > > - John > > > On Thu, May 21, 2009 at 10:33 AM, jim holtman <jholtman at gmail.com> wrote: >> Assuming that you get the list of indices into iData for the criteria, then >> you can use that to get the appropriate rows: >> >> indx <- which(iData >5)? # or whatever your criteria is >> DataSeq[indx,, drop=FALSE]? # gives you a subset matrix of just the rows you >> are interested in. >> >> On Thu, May 21, 2009 at 10:10 AM, tsunhin wong <thjwong at gmail.com> wrote: >>> >>> Dear R Users, >>> >>> I have created a 1500 x 20000 data frame - DataSeq. Each of the 1500 >>> rows represents a data sequence. >>> I have another data frame iData that stores the information of these >>> 1500 data sequences in the same order, for example, condition, gender, >>> etc. >>> >>> If I use "subset" to select certain groups within iData according to >>> some criteria that I have set, e.g. condition, gender >>> Then how can I used the retrieved subset of iData to point to and >>> retrieve corresponding rows in the DataSeq data.frame for >>> manipulations and analysis? >>> >>> I hope some of you can give me some idea! >>> Thank you very much!!! >>> >>> - John >>> >>> ______________________________________________ >>> 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 >> Cincinnati, OH >> +1 513 646 9390 >> >> What is the problem that you are trying to solve? >> >