[R] lapply to multivariate function?
Rui Barradas
ruipbarradas at sapo.pt
Sun Sep 1 21:00:03 CEST 2013
Hello,
Your example doesn't really run, but for what I've seen, if your second
data frame is named dat2, something along the lines of
n <- nrow(dat2)
res <- list("vector", n)
for(i in 1:n){
res[[i]] <- with(dat2, DataVideoActionT(anon_ID[i], Time1[i], TimeM[i],
TimeL[i]))
}
do.call(rbind, res)
Rui Barradas
Em 01-09-2013 17:40, Ignacio Martinez escreveu:
> I hope this reproduceble example helps understand what I'm trying to do.
>
> This is the function:
>
> # Make Data Frame for video actions between given times for user X
> DataVideoActionT <- function (userX, Time1, Time2, Time3){
> #Get data for user X
> videoActionsX<-subset(videoLectureActions, username==userX)
> #Time1 = before first attempt
> videoActionsX_T1<-subset(videoActionsX, eventTimestamp<Time1)
> #Time2 = before best attemp
> videoActionsX_T2<-subset(videoActionsX, eventTimestamp<Time2 &
> eventTimestamp>Time1)
> #Time3= before last attemp
> videoActionsX_T3<-subset(videoActionsX, eventTimestamp<Time3 &
> eventTimestamp>Time1)
>
> error1 = sum(videoActionsX_T1$type==" error ")
> pause1 = sum(videoActionsX_T1$type==" pause ")
> play1 = sum(videoActionsX_T1$type==" play ")
> ratechange1 = sum(videoActionsX_T1$type==" ratechange ")
> seeked1 = sum(videoActionsX_T1$type==" seeked ")
> stalled1 = sum(videoActionsX_T1$type==" stalled ")
>
> error2 = sum(videoActionsX_T2$type==" error ")
> pause2 = sum(videoActionsX_T2$type==" pause ")
> play2 = sum(videoActionsX_T2$type==" play ")
> ratechange2 = sum(videoActionsX_T2$type==" ratechange ")
> seeked2 = sum(videoActionsX_T2$type==" seeked ")
> stalled2 = sum(videoActionsX_T2$type==" stalled ")
>
> error3 = sum(videoActionsX_T3$type==" error ")
> pause3 = sum(videoActionsX_T3$type==" pause ")
> play3 = sum(videoActionsX_T3$type==" play ")
> ratechange3 = sum(videoActionsX_T3$type==" ratechange ")
> seeked3 = sum(videoActionsX_T3$type==" seeked ")
> stalled3 = sum(videoActionsX_T3$type==" stalled ")
>
> data<-data.frame(anon_ID=userX,
> error1 = error1,
> pause1 = pause1,
> play1 = play1,
> ratechange1 = ratechange1,
> seeked1=seeked1,
> stalled1=stalled1,
> error2 = error2,
> pause2 = pause2,
> play2 = play2,
> ratechange2 = ratechange2,
> seeked2 =seeked2,
> stalled2 = stalled2,
> error3 = error3,
> pause3 = pause3,
> play3 = play3,
> ratechange3 = ratechange3,
> seeked3 = seeked3,
> stalled3 = stalled3)
> return(data)
> }
>
> This is the videoActionsX dataframe:
>
> structure(list(username = c("exampleID1", "exampleID1", "exampleID1",
> "exampleID2", "exampleID2", "exampleID2",
> "exampleID3", "exampleID3",
> "exampleID3", "exampleID3"), currentTime =
> c("103.701247", "103.701247",
>
> "107.543877", "107.543877", "116.456507", "116.456507", "119.987188",
>
> "177.816693", "183.417124", "183.417124"), playbackRate = c("null",
>
> "null", "null",
> "null", "null", "null", "null", "null", "null",
>
> "null"), pause =
> c("true", "false", "true", "false", "true",
>
>
> "false", "true", "false", "true", "false"), error = c("null",
>
>
> "null", "null",
> "null", "null", "null", "null", "null", "null",
>
>
> "null"), networkState
> = c("1", "1", "1", "1", "1", "1", "1",
>
>
>
> "1", "1", "1"), readyState = c("4", "4", "4", "4", "4", "4",
>
>
>
> "4", "4", "4", "4"), lectureID =
> c("exampleLectureID1", "exampleLectureID1",
>
>
>
>
> "exampleLectureID1", "exampleLectureID1", "exampleLectureID1",
>
>
>
>
> "exampleLectureID1", "exampleLectureID1", "exampleLectureID1",
>
>
>
>
> "exampleLectureID1", "exampleLectureID1"), eventTimestamp = c("2013-03-04
> 18:51:49",
>
>
>
>
> "2013-03-04
> 18:51:50", "2013-03-04 18:51:54", "2013-03-04 18:51:56",
>
>
>
>
> "2013-03-04
> 18:52:05", "2013-03-04 18:52:07", "2013-03-04 18:52:11",
>
>
>
>
> "2013-03-04
> 18:59:17", "2013-03-04 18:59:23", "2013-03-04 18:59:31"
>
>
>
> ),
> initTimestamp = c("2013-03-04 18:44:15", "2013-03-04 18:44:15",
>
>
>
>
> "2013-03-04 18:44:15", "2013-03-04 18:44:15", "2013-03-04
> 18:44:15",
>
>
>
>
> "2013-03-04 18:44:15", "2013-03-04 18:44:15", "2013-03-04
> 18:44:15",
>
>
>
>
> "2013-03-04 18:44:15", "2013-03-04 18:44:15"), type = c("
> pause ",
>
>
>
>
> "
> play ", " pause ", " play ", " pause ", " play ", " pause ",
>
>
>
>
> "
> play ", " pause ", " play "), prevTime = c("103.701247 ", "103.701247 ",
>
>
>
>
>
> "107.543877 ", "107.543877 ",
> "116.456507 ", "116.456507 ", "119.987188 ",
>
>
>
>
>
> "177.816693 ", "183.417124 ",
> "183.417124 ")), .Names = c("username",
>
>
>
>
>
>
> "currentTime", "playbackRate", "pause", "error",
> "networkState",
>
>
>
>
>
>
> "readyState", "lectureID", "eventTimestamp",
> "initTimestamp",
>
>
>
>
>
>
> "type", "prevTime"), row.names = c(1L, 2L, 5L, 6L,
> 17L, 21L,
>
>
>
>
>
>
> 28L, 936L, 957L,
> 988L), class = "data.frame")
>
>
>
> But with over 2000 observation.
>
> And this is the other data frame
>
> structure(list(anon_ID = c("exampleID1", "exampleID2", "exampleID3" ),
> maxGrade = c(10, 5, 10), firstGrade = c(10, 5, 8), lastGrade = c(10,
> 5, 10), total_submissions = c(1L, 1L, 3L), Time1 =
> structure(c(1361993741, 1362356090, 1362357401), class = c("POSIXct",
> "POSIXt"), tzone = ""), TimeM = structure(c(1361993741, 1362356090,
> 1362492744), class = c("POSIXct", "POSIXt"), tzone = ""), TimeL =
> structure(c(1361993741, 1362356090, 1362492744), class = c("POSIXct",
> "POSIXt"), tzone = "")), .Names = c("anon_ID", "maxGrade",
> "firstGrade", "lastGrade", "total_submissions", "Time1", "TimeM",
> "TimeL"), row.names = c(NA, 3L), class = "data.frame")
>
>
> But with a lot more observations.
>
>
> What I want to do is to call function (userX, Time1, Time2, Time3)
> for all the user in the second data frame where Time1=Time1,
> Time2=TimeM, Time3=TimeL
>
>
> I hope that is more clear.
>
>
> Thanks a lot for all the help!
>
>
>
> On Sun, Sep 1, 2013 at 11:33 AM, Bert Gunter <gunter.berton at gene.com> wrote:
>
>> Oh, another possibility is ?mapply, which I should have pointed out in my
>> previous reply. Sorry.
>>
>> -- Bert
>>
>>
>> On Sun, Sep 1, 2013 at 8:30 AM, Bert Gunter <bgunter at gene.com> wrote:
>>
>>> Rui et.al.:
>>>
>>> But apply will not work if the data frame has columns of different
>>> classes/types, as appears to be the case here. Viz, from ?apply:
>>>
>>> "If X is not an array but an object of a class with a non-null dim<http://127.0.0.1:12824/help/library/base/help/dim>
>>> value (such as a data frame),apply attempts to coerce it to an array via
>>> as.matrix if it is two-dimensional (e.g., a data frame) or via as.array.
>>> "
>>>
>>> Simply looping by rows (via for() ) appears to be the simplest and
>>> probably fastest solution. There are other ways via tapply() and friends,
>>> but these are also essentially loops and are likely to incur some
>>> additional overhead.
>>>
>>> All assuming I understand what the OP has requested, of course.
>>>
>>> Cheers,
>>>
>>> Bert
>>>
>>>
>>> On Sun, Sep 1, 2013 at 7:31 AM, Rui Barradas <ruipbarradas at sapo.pt>wrote:
>>>
>>>> Hello,
>>>>
>>>> Maybe you need apply, not lapply. It seems you want to apply() a
>>>> function to the first dimension of your data.frame, something like
>>>>
>>>> apply(dat, 1, fun) #apply by rows
>>>>
>>>>
>>>> Hope this helps,
>>>>
>>>> Rui Barradas
>>>>
>>>> Em 01-09-2013 15:00, Ignacio Martinez escreveu:
>>>>
>>>>> I have a Data Frame that contains, between other things, the following
>>>>> fields: userX, Time1, Time2, Time3. The number of observations is 2000.
>>>>>
>>>>> I have a function that has as inputs userX, Time1, Time2, Time3 and
>>>>> return
>>>>> a data frame with 1 observation and 19 variables.
>>>>>
>>>>> I want to apply that function to all the observations of the first data
>>>>> frame to make a new data frame with 2000 observations and 19 variables.
>>>>>
>>>>> I thought about using lapply, but if I understand correctly, it only
>>>>> takes
>>>>> one variable.
>>>>>
>>>>> Can somebody point me in the right direction?
>>>>>
>>>>> Thanks!
>>>>>
>>>>> [[alternative HTML version deleted]]
>>>>>
>>>>> ______________________________**________________
>>>>> R-help at r-project.org mailing list
>>>>> https://stat.ethz.ch/mailman/**listinfo/r-help<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.
>>>>>
>>>>>
>>>> ______________________________**________________
>>>> R-help at r-project.org mailing list
>>>> https://stat.ethz.ch/mailman/**listinfo/r-help<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.
>>>>
>>>
>>>
>>>
>>> --
>>>
>>> Bert Gunter
>>> Genentech Nonclinical Biostatistics
>>>
>>> Internal Contact Info:
>>> Phone: 467-7374
>>> Website:
>>>
>>> http://pharmadevelopment.roche.com/index/pdb/pdb-functional-groups/pdb-biostatistics/pdb-ncb-home.htm
>>>
>>>
>>
>>
>>
>> --
>>
>> Bert Gunter
>> Genentech Nonclinical Biostatistics
>>
>> Internal Contact Info:
>> Phone: 467-7374
>> Website:
>>
>> http://pharmadevelopment.roche.com/index/pdb/pdb-functional-groups/pdb-biostatistics/pdb-ncb-home.htm
>>
>>
>
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