subset - R help- creating a sub-data set -

i have large dataset (38053 rows= transcripts, 39 columns=samples) want make new dataset sample values group of transcripts.

x= data1["698568366",] 

works single transcript, "698568366" name of transcript

but instead of 1 @ time, want use lits of 3000

i thought should able use:

data1[data1[,1] %in% 3000_m,] 

where 3000_m list in matrix form,

but keep getting back

  <0 rows> (or row.names mit length 0) 

here arrays , b:

a = c(1:10) b = c(11:20) 

creating dataframe them:

df = data.frame(a, b) 

here index array:

ind = c(3, 5, 7) 

select rows indexed ind:

new_df = df[ind,] 

you can't use multidimensional arrays index (as far know).