using awk with column value conditions

Question

I\'m learning awk from The AWK Programming Language and I have a problem with one of the examples.

If I wanted to print $3 if $2 is equal to a value (e.g.1

Answer 1

If you're looking for a particular string, put quotes around it:

awk '$1 == "findtext" {print $3}'

Otherwise, awk will assume it's a variable name.

Answer 2

My awk version is 3.1.5.

Yes, the input file is space separated, no tabs.

According to arutaku's answer, here's what I tried that worked:

awk '$8 ~ "ClNonZ"{ print $3; }' test  
0.180467091
0.010615711
0.492569002


$ awk '$8 ~ "ClNonZ" { print $3}' test  
0.180467091
0.010615711
0.492569002

What didn't work(I don't know why and maybe due to my awk version:),

$awk '$8 ~ "^ClNonZ$"{ print $3; }' test
$awk '$8 == "ClNonZ" { print $3 }' test

Thank you all for your answers, comments and help!

Answer 3

Depending on the AWK implementation are you using == is ok or not.

Have you tried ~?. For example, if you want $1 to be "hello":

awk '$1 ~ /^hello$/{ print $3; }' <infile>

^ means $1 start, and $ is $1 end.

Answer 4

please try this

echo $VAR | grep ClNonZ | awk '{print $3}';

or

echo cat filename | grep ClNonZ | awk '{print $3}';

Answer 5

This method uses regexp, it should work:

awk '$2 ~ /findtext/ {print $3}' <infile>

Answer 6

This is more readable for me

awk '{if ($2 ~ /findtext/) print $3}' <infile>