Beefy Boxes and Bandwidth Generously Provided by pair Networks
XP is just a number

Comment on

( #3333=superdoc: print w/ replies, xml ) Need Help??
You're right, that's a bug. I think replacing the grep with a one distinguishing between two cases solves it. Here is the updated package:

use strict; use warnings; package FastRanges; sub new($$$) { my $class = shift; my $max_length = shift; my $ranges_a = shift; my @lookup; for ( @{$ranges_a} ) { my ( $start, $end ) = @$_; my @idx = $end >= $start ? $start .. $end : ( $start .. $max_length, 1 .. $end ); for my $i (@idx) { $lookup[$i] .= pack 'L', $end } } bless \@lookup, $class; } sub num_ranges_containing($$$) { my $self = shift; my ( $start, $end ) = @_; # query range coordinates return 0 unless ( defined $self->[$start] ) ; # no ranges overlap the start position of the query if ( $end >= $start ) { # query range is simple # any inverted range in {LOOKUP}[$start] must contain it, # and so does any simple range which ends at or after $end return 0 + grep { $_ < $start or $end <= $_ } unpack 'L*', $self->[$start]; } else { # query range is inverted # only inverted ranges in {LOOKUP}[$start] which also end # at of after $end contain it. simple ranges can't contain # the query range return 0 + grep { $_ < $start and $end <= $_ } unpack 'L*', $self->[$start]; } } 1;
Perhaps this could be done a bit more efficiently, I'm not sure.

Thanks for noting the bug, BrowserUK! I'm sure you saved me a lot of future frustration.

And if you indeed think it now works and also pretty much optimized, I'd be happy to get some ideas for the original question.

In reply to Re^6: Serializing a large object by daverave
in thread Serializing a large object by daverave

Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":

  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.
  • Log In?

    What's my password?
    Create A New User
    and the web crawler heard nothing...

    How do I use this? | Other CB clients
    Other Users?
    Others chanting in the Monastery: (8)
    As of 2015-11-27 10:48 GMT
    Find Nodes?
      Voting Booth?

      What would be the most significant thing to happen if a rope (or wire) tied the Earth and the Moon together?

      Results (724 votes), past polls