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Full Discussion: Bitwise comparison of cols
Top Forums Shell Programming and Scripting Bitwise comparison of cols Post 302872669 by RudiC on Saturday 9th of November 2013 06:24:27 AM
Old 11-09-2013
Sheer curiosity: having the main loop run to NF-1 only might yield a fraction of a percent run time reduction:
Code:
{for(i=1; i<NF; i++) ...

Unfortunately, replacing the
Code:
 if($i==$j) c[i,j]++

by
Code:
 c[i,j]+= ($i==$j)

increases run time dramatically, probably because the ++ operation is a register operation while the other is a full addition.
 

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IO::Async::Timer::Absolute(3pm) 			User Contributed Perl Documentation			   IO::Async::Timer::Absolute(3pm)

NAME
"IO::Async::Timer::Absolute" - event callback at a fixed future time SYNOPSIS
use IO::Async::Timer::Absolute; use POSIX qw( mktime ); use IO::Async::Loop; my $loop = IO::Async::Loop->new; my @time = gmtime; my $timer = IO::Async::Timer::Absolute->new( time => mktime( 0, 0, 0, $time[4]+1, $time[5], $time[6] ), on_expire => sub { print "It's midnight "; $loop->stop; }, ); $loop->add( $timer ); $loop->run; DESCRIPTION
This subclass of IO::Async::Timer implements one-shot events at a fixed time in the future. The object waits for a given timestamp, and invokes its callback at that point in the future. For a "Timer" object that waits for a delay relative to the time it is started, see instead IO::Async::Timer::Countdown. EVENTS
The following events are invoked, either using subclass methods or CODE references in parameters: on_expire Invoked when the timer expires. PARAMETERS
The following named parameters may be passed to "new" or "configure": on_expire => CODE CODE reference for the "on_expire" event. time => NUM The epoch time at which the timer will expire. Once constructed, the timer object will need to be added to the "Loop" before it will work. Unlike other timers, it does not make sense to "start" this object, because its expiry time is absolute, and not relative to the time it is started. AUTHOR
Paul Evans <leonerd@leonerd.org.uk> perl v5.14.2 2012-10-24 IO::Async::Timer::Absolute(3pm)
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