Re^2: Triangle Numbers Revisited

[Limbic~Region]

FoxtrotUniform,
The trouble with selecting a single number to benchmark from is that it may favor one method over the other. With this in mind, I created another rudimentary benchmark that shows the two methods are fairly equal:

First generate 5,000 random numbers between 1 .. 5_000_000

$ cat gen_targets.pl
#!/usr/bin/perl
use strict;
use warnings;
my $file = $ARGV[0] || 'targets.txt';
open (OUTPUT, '>', $file) or die "Unable to open $file for writing : $
+!";
print OUTPUT int rand 5_000_000, "\n" for 1 .. 5_000;

Next, I just modified our 2 scripts as follows:

my $file = $ARGV[0] || 'targets.txt';
open (INPUT, '<', $file) or die "Unable to open $file for reading : $!
+";

while ( <INPUT> ) {
    chomp;
    get_three( $_ );  # used your sub/calling convention
}

And finally, the results:

$ time ./lr.pl

real    1m0.706s
user    1m0.416s
sys     0m0.080s

$ time ./fu.pl

real    1m0.791s
user    1m0.326s
sys     0m0.220s

I haven't spent any time thinking about optimizations, but if I come up with any tomorrow I will post it along with a "real" benchmark.

[FoxtrotUniform]

The trouble with selecting a single number to benchmark from is that it may favor one method over the other.

Good catch. Another problem I ran into was that the load on my test system was varying (lab machine, someone was logged in remotely doing a bunch of matlab foolery), so I ended up getting quite different "real" time results with the same input... which is probably what a casual reader would check.

It would be interesting to know what kinds of inputs favour whose method, and (ideally) why.