I have an tximport object with 628 files. I want to subset to remove some samples and maintain the tximport data structure.

str(txi_object)
List of 4
$ abundance          : num [1:56928, 1:628] 14.125 0 15.221 12.45 0.765 ...
  ..- attr(*, "dimnames")=List of 2
  .. ..$ : chr [1:56928] "5S_rRNA" "5_8S_rRNA" "7SK" "A1BG" ...
  .. ..$ : chr [1:628] "20798913" "20914669" "50301125" "20149910" ...
$ counts             : num [1:56928, 1:628] 10.5 0 87.1 440 74.9 ...
  ..- attr(*, "dimnames")=List of 2
  .. ..$ : chr [1:56928] "5S_rRNA" "5_8S_rRNA" "7SK" "A1BG" ...
  .. ..$ : chr [1:628] "20798913" "20914669" "50301125" "20149910" ...
$ length             : num [1:56928, 1:628] 15.1 24.2 116.4 718.5 1990.3 ...
  ..- attr(*, "dimnames")=List of 2
  .. ..$ : chr [1:56928] "5S_rRNA" "5_8S_rRNA" "7SK" "A1BG" ...
  .. ..$ : chr [1:628] "20798913" "20914669" "50301125" "20149910" ...
$ countsFromAbundance: chr "no"

Final number of desired samples is 598 and I have the sample ids in a data frame. I tried mapply and ddply without much success. 

length(clean_samples$individualID)
[1] 598

Any ideas or suggestions would be helpful

regards

scanchi

p.s - I had to post the code as text as I was running into an language '"x" not supported issue.

It's just three matrices with dim (ngenes x nsamples), plus one extra list item,  so you should be able to simply subset. Using the example for tximport and removing the last sample I would do

example(tximport)
z <- lapply(txi, function(x) if(is.matrix(x)) return(x[,1:5]) else return(x))