Priority:   3rd 1st  2nd  4th
          ((1.0 0.1)(99.0 0.2))

##</code><code>##

my @coordinates_unsorted;

while ( <DATA> ) {
    push @coordinates_unsorted, [ m/([\d.]+)/g ];
}

my( @coordinates_sorted ) = 
    sort {
            $a->[1] <=> $b->[1]
        or  $a->[2] <=> $b->[2]
        or  $a->[0] <=> $b->[0]
        or  $a->[3] <=> $b->[3]
    } @coordinates_unsorted;

foreach my $coordinate_ref ( @coordinates_sorted ) {
    printf "((%2.1f %2.1f) (%2.1f %2.1f))\n", @{$coordinate_ref};
}


##</code><code>##

my( @coordinates_sorted ) =
    map{ 
        sprintf "((%2.1f %2.1f) (%2.1f %2.1f))\n", @{$_} 
    }
    sort {
            $a->[1] <=> $b->[1]
        or  $a->[2] <=> $b->[2]
        or  $a->[0] <=> $b->[0]
        or  $a->[3] <=> $b->[3]
    }
    map{ 
        [ m/([\d.]+)/g ] 
    }
    <DATA>;

{
    local $, = "\n";
    print @coordinates_sorted;
}