in reply to Access and modify specific element of tab delimited .txt file

Is there a way to print something into this first element?

I suspect you're after something more complex, but on the face of it, this seems to answer that question:

C:\test>type junk.dat
        A       B       C       D       E
A       1       1       1       1       1
B       1       1       1       1       1
C       1       1       1       1       1
D       1       1       1       1       1
E       1       1       1       1       1

C:\test>perl -plae" $.== 1 and $F[0] eq 'A' and $_ = 'ID' . $_" junk.d
+at
ID      A       B       C       D       E
A       1       1       1       1       1
B       1       1       1       1       1
C       1       1       1       1       1
D       1       1       1       1       1
E       1       1       1       1       1

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Re^2: Access and modify specific element of tab delimited .txt file
by K_Edw (Beadle) on Mar 30, 2016 at 12:24 UTC

    Thanks! This works well (after replacing " with '). It is slightly more complex in that $F[0] will not always eq 'A', so this could also be used:

    perl -plae '$.== 1 and $_ = 'ID' . $_'
[reply]
[d/l]
      Is there a way for it to simply check for any string (non-delimiter character) at all?

      Eily called it right:

      C:\test>type junk.dat
        A       B       C       D       E
A       1       1       1       1       1
B       1       1       1       1       1
C       1       1       1       1       1
D       1       1       1       1       1
E       1       1       1       1       1

C:\test>perl -F\t -plae"$.== 1 and $F[0] eq '' and $_ = 'ID' . $_" jun
+k.dat
ID      A       B       C       D       E
A       1       1       1       1       1
B       1       1       1       1       1
C       1       1       1       1       1
D       1       1       1       1       1
E       1       1       1       1       1

      [download]
      With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
      Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
      "Science is about questioning the status quo. Questioning authority". I knew I was on the right track :)
      In the absence of evidence, opinion is indistinguishable from prejudice.
[reply]
[d/l]

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