subset - Transposing and Merging datasets in R -

i sure there answers out there question can't seem find 1 works , im absolutely new r apologies redundancy!

so have huge dataset - 17k obs 35 variables. txt file imported , coerced as.matrix. 1st column has character values , rest 34 columns has numeric values.

structure -

>str(data_m)  chr [1:17933, 1:35] "rab12" "trim52" "c1orf86" "plac9" "morn3" "loc643783" "loc389541" "oaz2" ...  - attr(*, "dimnames")=list of 2   ..$ : null   ..$ : chr [1:35] "name" "x118" "x12" "x21" ... 

now there small long form dataset 2 columns - id , gender.

> str(data_maleids) 'data.frame':   24 obs. of  2 variables:  $ id    : factor w/ 34 levels "x118","x12","x21",..: 8 23 9 19 10 7 5 4 2 30 ...  $ gender: factor w/ 2 levels "female","male": 2 2 2 2 2 2 2 2 2 2 ...` 

eg. -

    row.names   id  gender 1   1           x37 male 2   2           x64 male 

all want subset 1st dataset ids ( x37, x64 etc) present in 2nd dataset.

i tried transposing bigger dataset gives me issues in terms of column names , can't seem way around this.

the first comment statement "the 1st column has character values , rest 34 columns has numeric values". data_m matrix, columns of same type. in case character. can see output of str(). think matrix in r vector arranged in several columns.

secondly advise use data.table package (you have install if not have yet) task. sketch of syntax this:

1. read data in. there nice function fread() in data.table package read data text files data.table object: data_m <- fread("file.name.txt")
2. key data_m variable id: setkey(data_m, id)
3. make vector of ids data_maleids: ids <- sort(unique(data_maleids$id)).
4. select case need: data_m[id %in% ids].