CODEWITHSUNDEEP
awk
user2256777
user2256777

Reputation: 87

How to use "awk" to modify the same line many times

I have a file,named score.tsv, the content is much more like:

1 jack 100 good
2 tom  50  notgood
....

and i want to modify the fourth field of the second line "notgood" to "fail" i used

awk -F"\t" '{if (NR==2) $4="fail";print > "temp.tsv"}' score.tsv

it works.

then i realized i need to change the second field of the second line to "lily" too. so i tried 

awk -F"\t" '{if (NR==2) $2="lily";print > "temp1.tsv"}' temp.tsv

it doesn't work.

the content of temp1.tsv is

1 jack 100 good
2 tom  50  fail lily
.....

how can i change the fields in one line of a file one by one? thanks

Upvotes: 0

Views: 53

Answers (1)

Kent
Kent

Reputation: 195219

the problem is, in your first command nogood->fail, you didn't assgin OFS. so that in your tmp.txt, it is NOT <tab> separated. so in your 2nd command, the $2 actually didn't exist, awk will append lily to the 2nd line.

try this two lines:

awk -F"\t" -v OFS="\t" '{if (NR==2) $4="fail";print > "temp.tsv"}' score.tsv
awk -F"\t" -v OFS="\t" '{if (NR==2) $2="lily";print > "temp1.tsv"}' temp.tsv

Upvotes: 3

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