remove lines where a field's value is less than or equal to 3 - sed or awk?
49,071
You almost got it.
awk '(NR>1) && ($8 > 2 ) ' foo > bar
where
NRis number of record (that is number of line)$8is eight field&&is logical andfoois the original file, unchangedbarresulting file- implicit default action is to print the current input line
Note that header is striped from foo to bar, to keep it
awk '(NR==1) || ($8 > 2 ) ' foo > bar
where
||is logical or- input line is printed if NR==1 or if $8 > 2
Update #1
To specify a range
( ($8 >= -4) && ( $8 <= 4 ) )8th field from -4 to 4(NR == 1 ) || ( ($8 >= -4) && ( $8 <= 4 ) )same, including header
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Unix & Linux: remove lines where a field's value is less than or equal to 3 - sed or awk?
Author by
geokrowding
Updated on September 18, 2022Comments
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geokrowding over 1 year
I need to remove every line that has a value of 2 or less in the 8th field (column).
My data looks like this:
12-31 Airport 189 379 41 49.70946503 -124.91377258 2 2880 30.8 01-01 AlberniElementary 165 331 16 49.26100922 -124.80662537 4 5760 26.1 01-09 BamfieldMarine 161 323 23 48.83490372 -125.13572693 2 2875 27.4 01-10 BamfieldMarine 161 323 23 48.83490372 -125.13572693 3 3068 38.6I understand that using awk I can strip off the values desired and print them to another file, and I understand that sed would edit the current file. In either case, I need to retain the original file.
Note: Please provide thorough explanations with your solutions. It is not suffice to just write the command, please annotate suggestions.
Further note: The data has a header line, so most likely solution will need to
awk 'FNR >1'
I suppose?
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geokrowding about 9 yearsGreat answer: simple yet thorough, thanks. Just so i'm clear, the difference between FNR and NR in this case is nothing, correct? I have read the man page where it explains: NR ordinal number of the current record & FNR ordinal number of the current record in the current file. So I understand these being equal in this case, I think :)
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Арсений Черенков about 9 yearsIf you have one file, FNR is always NR, if file1 has 10 lines, first line of file2 would have NR=11 and FNR=1
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Giles almost 8 yearsHi I want to do something similar but accept everything in a range of -4 to 4. how would I go about doing this, as this is the only way I can think of doing it currently awk '(NR==1) || ($8 = [-4-4] ) ' foo > bar
