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in reply to Re: Is there any efficient way i can take out a specific column from hundreds of files and put it in one file?
in thread Is there any efficient way i can take out a specific column from hundreds of files and put it in one file?

This results in a file with 2 columns and 1,000,000 rows, right? I'm not entirely sure, but I think that OP wants the final file to have 1000 + 1 columns and 1000 rows. Maybe...
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Re^3: Is there any efficient way i can take out a specific column from hundreds of files and put it in one file?
by coolda (Novice) on Sep 28, 2014 at 19:54 UTC
    Sorry for not writing a detailed description of what i am working on. So i have thousands of files in a tab delimited format saved in one folder. Each file has a format of 2000 by 10 table What i want to do right now is create new file with the data i want. So the format of each file follows .. 
    Gene exp1 exp2 exp3 exp4 ...
1    1050 2020 100  100
2    100  100  100  100
3    224  11   11   11
4    11   15   555  444
5    22   51   55   555
6    55   55   55   555
...

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    From the first file i read, I want to extract two columns for example I want 'Gene' and 'exp4' columns and put it in a new file. And from the rest of the other files, I want to extract 'exp4' column only and add on the right side of the two columns i extracted from the first file. So the final format would look like 
    Gene file1 exp4 file2 exp4 file3 exp4 file4 exp4....
1       100         200      155         144
2        22         55       222         444
3
4
5
6
.
.

    [download]
    So it will have a 2000 by thousands(number of my files) table as a result. I am a beginner in programming and especially in perl. help me please..
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[d/l]
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      In that case, the second code snippet in my previous answer should do the trick if you are on Linux or OS X.
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