Extract one line from every 3 lines


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# 1  
Extract one line from every 3 lines

Hi,

I am trying with the below command to extract every line after 3 lines in a file.

Somehow I am failing to achieve it. Why?

Code:
awk '!($1%3)'

# 2  
Like this?
Code:
$> cat infile
1
2
3
4
5
6
7
$> awk 'NR % 3 == 0' infile
3
6

# 3  
Code:
awk '!(NR%4)' infile



---------- Post updated at 06:50 AM ---------- Previous update was at 06:49 AM ----------

Use gawk, nawk or /usr/xpg4/bin/awk on Solaris.

Last edited by danmero; 12-23-2009 at 09:51 AM.. Reason: change from third to forth as per original request
# 4  
Do you mean like this:
Code:
awk 'NR>3' infile

# 5  
Quote:
Originally Posted by royalibrahim
Hi,

I am trying with the below command to extract every line after 3 lines in a file.
That could be the 4th line, the 8th line and so fort. Please clarify your question.
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