Commands by genatomics (1)

  • awk zero pad last field in variable-length record

    The sample output shows each record/row with the last field zero-padded to 26 digits. For testing, I used (L)ine and field/column numbers.... Line 4, field2 = L42, etc up to the last field where I just used line numbers X 4. I had some whitespace-delimited files with variable-length records/rows (having 4 - 5 fields/columns) which required reformatting by zero-padding the last field to 26 digits. This requires setting NF (Not $NF) as an awk variable, with a simple conditional that assumes that any line where (N)umber of (F)ields does NOT equal 4 has a NF of 5. If needed, more conditional checks can be added, and the "NF" changed to any field ($1, $5, etc). Show Sample Output


    0
    awk '{var = sprintf(NF); if (var == 4) printf "%s %s %s %026d\n" , $1,$2,$3,$4; else printf "%s %s %s %s %026d\n" , $1,$2,$3,$4,$5}' yourfilegoes.here >> yournewfilegoes.here
    genatomics · 2014-12-20 02:53:35 8

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