[R] Help with lapply and tapply

[Rui Barradas]

Also, the OP's FUN1 is NOT a function. It's the result of a function 
call. A function would be

FUN1 <- function(x) EM_mixture_copula(...)

Hope this helps,

Rui Barradas

Em 11-03-2017 10:29, Michael Hannon escreveu:
> I think Bert's advice is sound.  Let me add a few, miscellaneous comments:
>
> (1) Some people find "by" easier than "tapply".
> (2) The "apply" function can, as I'm sure you (Bert) know, iterate
> over a matrix.
> (3) Hadley probably has better ways to do all of this (it's hard to keep up).
>
> -- Mike
>
>
> On Fri, Mar 10, 2017 at 9:22 PM, Bert Gunter <bgunter.4567 at gmail.com> wrote:
>> In short, you really need to study the Help files carefully for both,
>> as you are using both tapply and lapply incorrectly. If that doesn't
>> work, I think you should spend some time with one of the many
>> excellent R tutorials on the web. You need to beef up your
>> understanding of the syntax.
>>
>> But briefly:
>>
>> 1) the tapply call must be of the form tapply(x, fac, fun) where x is
>> atomic (i.e. a vector) and fac is a factor that splits x into groups.
>> You have obviously got the call all wrong.
>>
>> 2) And in the second, X must be a list or vector, not a matrix and the
>> function needs to have its elements as an argument, something like FUN
>> = function(x)FUN1(x, ... your other arguments...)
>>
>> Cheers,
>> Bert
>>
>>
>> Bert Gunter
>>
>> "The trouble with having an open mind is that people keep coming along
>> and sticking things into it."
>> -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip )
>>
>>
>> On Fri, Mar 10, 2017 at 2:40 PM, Fadhah <fadeh2013 at gmail.com> wrote:
>>> Dear all,
>>>
>>> Thank you in advance for your time and help. I quite new to R and face a problem with lapply and tapply functions.
>>> I simulated data and run the simulation 10 times to get 10 different simulated data. I have also built up my function and would like to apply this function to these 10 different data without repeating the code for 10 times. I now that we can use a loop family functions in R such as lapply or tapply functions. I tried both of them but both of them did not work. My data was stored as vector mode list.
>>>
>>> Here is my data:
>>>
>>> library(VineCopula)
>>> library(copula)
>>> Runs= 10 Saveas = vector(mode = "list", length = Runs)
>>>   pb <- txtProgressBar(min = 0, max = Runs, style = 3)
>>> for(j in 1:Runs){
>>>   setTxtProgressBar(pb, j)
>>> N=2000
>>>   dim=dim
>>>   U=runif(N, min=0,max=1)
>>>   X = matrix(NA, nrow=N, ncol=2)
>>> inds <- U < 0.7
>>>   X[inds, ] <- rCopula(sum(inds), claytonCopula(1, dim=2))
>>>   X[!inds, ] <- rCopula(N - sum(inds), frankCopula(4, dim=2))
>>> Saveas[[j]] = X }
>>> Then I built my function. I would like to apply this function to the 10 simulation run. That is I have 10 simulated data and would like to run my function to these data. I tried lapply and tapply function but I got  errors.
>>> This is my function:
>>>
>>> FUN1 <- EM_mixture_copula(data = Saveas[[j]],pi_1=pi_1,pi_2=pi_2,theta = theta,                Theta=Theta, tol = .00001, maxit = 1000)
>>> Here is my tries with the errors that I got:
>>>
>>>> result <- tapply(X,FUN1,simplify = T)
>>> Error in tapply(X, FUN, simplify = T) : arguments must have same length.
>>>
>>>> Result <– lapply(X,FUN1)
>>> Error in get(as.character(FUN), mode = "function", envir = envir) : object 'F' of mode 'function' was not found.
>>>
>>>
>>>
>>> Once I got the result, I would like to have a summary statistics of my function for each run. So, can I use
>>>
>>> Summary(result) ?
>>>
>>> Any help, please?
>>> Kinds regards,
>>> Fadhah
>>>
>>> Sent from my iPhone
>>>          [[alternative HTML version deleted]]
>>>
>>> ______________________________________________
>>> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
>>> 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.
>>
>> ______________________________________________
>> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
>> 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.
>
> ______________________________________________
> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> 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.
>