Unless I've mis-interpreted it, having done the hard work as posited by toolic, the problem is now down to the printed representation - maybe this, or something not unlike it, is more along the lines of what you're seeking... 
use warnings;
use strict;
use Data::Dumper;

my %Diag;
while (<DATA>) {
    my ($name, $val) = split;
    push @{ $Diag{$name} }, $val;
}

print "$_ => " . join(' ', @{$Diag{$_}}) . "\n" for keys %Diag;

__DATA__
Name1 1234
Name2 9999
Name1 5514
Name3 5415
Name2 6419

[download]

A user level that continues to overstate my experience :-))

In reply to Re^3: Hashes of arrays populated from a Text File by Bloodnok
in thread Hashes of arrays populated from a Text File by Raya4505

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