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Print lines based on line number and specified condition

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# 1  
Old 11-06-2014
Print lines based on line number and specified condition


I have a file like below.


I would like to print or copied to a file based of line count in perl

If I gave a condition 1 to 3 then it should iterate over above file and print 1 to 3 and then again 1 to 3 etc.

output should be


Last edited by jim mcnamara; 11-06-2014 at 08:06 AM..
# 2  
Old 11-06-2014
Hello Anjan,

Following may help you in same.

awk -F, '{for(i=1;i<=NF;i++){{S=S?S OFS $i:$i} if(i%3==0){print S;S=""}}}' OFS=, Input_file

Output will be as follows.

EDIT: I am sorry Jim, seems we have posted on same time, if possible kindly delete my post, as you have OP a question.

R. Singh

Last edited by RavinderSingh13; 11-06-2014 at 08:08 AM.. Reason: Adding apology comment to Jim
# 3  
Old 11-06-2014
What have you tried so far?
# 4  
Old 11-06-2014
I have tried it in perl.


use warnings;
use strict;

my @result;

my $filename = "new_num.txt";

my $i;
unlink $filename;

while(<>) {

$_ =~ s/,/\n/g;

if (($. == 1) .. ($. == 3)) {

#$_ =~ s/^ //g;

push (@result,$_);

print "@result";

foreach $i (@result) {

$i =~ s/\n/,/g;

open FILE,">>$filename" or die "Cannot read the file $filename: $!\n";

print FILE "$i";

#print FILE "\n";

@result = ();

#goto START;


ravinder singh can you please explain me your awk code.

Last edited by Anjan1; 11-06-2014 at 08:37 AM.. Reason: code change
# 5  
Old 11-06-2014
input=( {a..z} )

while [[ $C -lt $max ]];do
	while [[ $count -lt $limit ]];do
		out+=" ${input[$C]}"
	echo "$out" ; out=""

sh ~/file1.txt 
 a b c
 d e f
 g h i
 j k l
 m n o
 p q r
 s t u
 v w x
 y z

Hope this helps
# 6  
Old 12-30-2014
its not printing entire contents in a file. If a file has 1,2,3,4,5,6,7.

When I use awk code given by ravindersingh its giving output as

awk -F, '{for(i=1;i<=NF;i++){{S=S?S OFS $i:$i} if(i%3==0){print S;S=""}}}' OFS=, Input_file


not printing 7
# 7  
Old 12-30-2014
Hello Anjan1,

Kindly try following and let me know if this helps.
xargs -d"," -n3 Input_file

Output will be as follows.
1 2 3
4 5 6

R. Singh

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