How to find those files name which contains specific symbol i.e. underscore sign in column2?

Question

[sidrarafi89]

i have 5000 files (name as: tni00001.keg, eco00001.keg etc) which contains underscre sign in 2nd column inside the many files (W909_00110). after the underscore sign, the number (i.e.00110) is actually represent the enzyme ID but some file out of 5000 donot contain this underscore sign in between the IDs.so now i want to extract those files names (like abc00001.keg) which don’t contains underscore sign _ in 2nd column of each files.

Example: keg file look like this from inside

D      W909_00110 glk; glucokinase      K00845 glk; glucokinase [EC:2.7.1.2]

D      W909_17905 pgi; glucose-6-phosphate isomerase    K01810 GPI; glucose-6-phosphate isomerase [EC:5.3.1.9]

D      W909_19315 6-phosphofructokinase K00850 pfkA; 6-phosphofructokinase 1 [EC:2.7.1.11]

[GenoMax]

i want to extract those files names (like abc00001.keg) which don’t contains underscore sign _ in 2nd column of each files.

Is absence of _ consistent for all lines in these files or only some records may not have _number?

[sidrarafi89]

total 5000 files and some files not have this underscore sign in between the IDs. how many files that donot conatins this sign inside, that's what i want to know and extract all these files names.

[GenoMax]

Clarification I was asking for is do all records in that file of interest not have a _ or only some.

[zx8754]

Crossposted:

https://stackoverflow.com/q/57799730/680068

[Joe]

Are these fields all tab separated?

[Friederike]

may I ask what the ultimate goal is? I.e. why are you specifically interested in files where the underscore is missing?

Answer 1

[bruce.moran]

so now i want to extract those files names (like abc00001.keg) which don’t contains underscore sign _ in 2nd column of each files.

for x in *.keg; do
  TEST=$(cut -f 2 $x | grep _ | head -n1)
  if [[ $TEST == "" ]];then
    echo $x;
  fi
done

Answer 2

[zx8754]

Something like this (not tested):

sapply(list.files("path/to/files", "*.keg", full.names = TRUE), 
       function(i){
         d <- read.table(i)
         if(!all(grepl("_", d[, 2]))){ 
           i 
           # maybe use basename(i) to return just the filename without path
         } else { NULL }
       })

[sidrarafi89]

it give me the following error ./script.sh: line 1: syntax error near unexpected token list.files' ./script.sh: line 1:sapply(list.files("/home/reaz/Documents/dump/bacteria/keggdatabase-uniq", "*.keg", full.names = TRUE), '

[rizoic]

The answer by @zx8754 is in R you will need to save it as a .R file and then execute it.

[sidrarafi89]

it still show me an error: Error in scan(file = file, what = what, sep = sep, quote = quote, dec = dec, : line 2 did not have 3 elements Calls: sapply -> lapply -> FUN -> read.table -> scan Execution halted

[zx8754]

You need to break it down, run the example code row by row, and see where it is failing. My guess is list.files is not finding any files.