range of lines

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

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Re: range of lines by Fletch (Bishop) on Jun 21, 2004 at 13:19 UTC
`while( <IN> ) { if( /zagnork/ ) { print scalar <IN> for 1..5; } }` [download]	[reply] [d/l]
Re: range of lines by kesterkester (Hermit) on Jun 21, 2004 at 13:23 UTC
This probably isn't the most clever way, but it'll do the job: set a counter to the number of lines you want to print out after data matches the pattern, and then 1) print out the line if the counter is positive, and 2) decrement the counter for each line that's printed out. `use warnings; use strict; my $nLines = 0; while (<DATA>) { $nLines = 5 if /kjkjkjkj/; print if $nLines-- > 0; } __DATA__ 1asdfasdf 2asdfasdf 3kjkjkjkjkj 4asdfasdf 5asdfasdf 6asdfasdf 7asdfasdf 8asdfasdf 9asdfasdf 10asdfasdf` [download] Outputs: 3kjkjkjkjkj 4asdfasdf 5asdfasdf 6asdfasdf 7asdfasdf	[reply] [d/l]
Re: range of lines by artist (Parson) on Jun 21, 2004 at 15:39 UTC
On Unix, you may be able to accomplish with this. `grep -A5 pattern file` [download]	[reply] [d/l]
Re: range of lines by delirium (Chaplain) on Jun 21, 2004 at 15:20 UTC
If you happen to want the matching line printed in addition to the 5 lines after it, you could use the .. operator like so: `perl -ne 'print if /PATTERN/ .. ++$c%6==0;' file.txt`	[reply] [d/l]
Re^2: range of lines by kesterkester (Hermit) on Jun 22, 2004 at 13:10 UTC
Ahhh, that's a very clever way to do it. ++delirium!	[reply]