use Perl

MIT E51-376 (or thereabouts), June 10th, 7:15pm ET. directions

refreshments courtesy of CIDC.com (who is recruiting perl mongers locally)

Boston.pm will have a tech meeting on Tuesday, February 12, at MIT, in building E51, room 376 (directions below), starting at 7:15pm.

Martin Owens will be giving a presentation on one of his modules, Data::Validate::XSD.

http://search.cpan.org/~doctormo/Data-Validate-XSD-1.03/

This module allows the definition of complex data structures and allows validation against them. It is based on the W3C XSD definition, and does not use XML. Features include mirrored-errors (which describe failures in terms of their structural position and the effect on the parents) and minimal dependencies. Use cases include validation data sent to a webpage, validating data used in object creation, and validating XML parsed data.

RSVP to [Ronald] if you're planning to attend - rjk-bostonpm (at) tamias (d*t) net.

Pizza and soda for this meeting will be sponsored by Cambridge Interactive Development Corp. Thanks CIDC!

Ronald

[Forward by Bill / n1vux ]

For more information about Boston Perl Mongers, or to subscribe to one of
our mailing lists, visit our website at http://boston.pm.org/

Using Perl, Postgres and SQL to build a Comprehensive, Searchable Database of Firewall Activity on a Checkpoint firewall on the Cheap by Thomas Munn on 23/12/07

One of the biggest problems in computer security is how to deal with logs. Firewall logs are especially difficult because they often run into the tens to hundreds of gigabytes, and searching them requires expensive, proprietary packages. The purpose of this paper is to help instruct the reader in how to use Postgres and Perl to have a queryable database using checkpoint log files. I do not cover other firewalls but the ideas herein could be applied to almost any firewall supporting output to text files. This paper will give the security practitioner to perform data mining on otherwise useless logfiles. Using the methods described in this document enabled the author to query for almost anything imaginable from a total of 450,000,000 records in under ten minutes. The cost: The cost of the hardware.

Above reviewlet PDF

(Isn't something old, something new, for a different celebration?)

They mention in passing I18N as a key feature for prefering Perl to say PHP -- multiple languages in one website.

My reply there

Happy Standard Time! Don't forget to change the smoke detector batteries today too.

Public safety used to push the Change your Clock, Change your Batteries. The twice a year tweak everything ritual as a convenient reminder that it's best to change smoke/CO detector batteries 2x/year is good, but with DST extended into November (which gives extra daylight for Trick-or-Treat, good),connection of Fire Prevention Month (October) and DST-FireAlarm is more tenuous.

So if you did it in October, please ignore this message :-)

Otherwise, just consider today October 35th and the chore somewhat overdue.

  I have a pricey LED flashlight that wilk run for months on the leftover power, so I can recycle the batts too. (Marked "U" for used with grease pencil when swapped out.) Which means one or the other is free :-) Fits in pocket. "Off" isn't, but only "very low" so you can find it when city power fails

I g0t mine, the old Elight model, from http://www.eventors-now.com/default.asp at local ham shows, but they new models are available mailorder too
http://flashlightsunlimited.com/safelight.htm is newest model with new lower price http://flashlightsunlimited.com/survival.htm like the original

Thanks to Andy and O'Reilly for sponsoring the doorprizes for the installfest.

Previously I've blogged a couple of Compute Pi in Perl items here --- http://use.perl.org/~n1vux/journal/28505 and http://use.perl.org/~n1vux/journal/32292.

My use.perl.org user #1492 appears at the 19,915th position in Pi's decimal fraction http://www.angio.net/pi/bigpi.cgi.

There are Pi Day observances at Math Departments, schools, and science museums all over http://www.google.com/search?hl=en&q=pi+day.

I'm somewhat surprised that Math::BigFloat doesn't have an AntiLog function for Euler's base 'e' (natural exponent). Hard coding it as a constant isn't terrible, but not nice either. I suppose I could compute it too ...

#!/usr/local/bin/perl

###
# Adaptation of my prior program to test XKCD's formulas 2007-01-31
# (9^2 + 19^2/22)^(1/4) = PI
# (e^pi - pi) = 20 - delta
# http://xkcd.com/c217.html
####

use strict;
use warnings;
use Math::BigFloat;

my $DIGS= ($ARGV[0]||10);
Math::BigFloat->div_scale($DIGS+5);

# (9^2 + 19^2/22) = PI
print "(9^2 + 19^2/22) = PI ? \n";
my $pi = new Math::BigFloat '9';
$pi->bpow(2);
$pi->bpow(2);

my $term= new Math::BigFloat'19';
$pi->badd($term->bpow(2)->bdiv(22));

# $pi->bsqrt()->bsqrt();
$pi->broot(4);

# compare to known-good from bottom of file
my $PI=(new Math::BigFloat <DATA>);
my $good=$PI->copy()->round($DIGS+2);
print $good, "\n";
print $pi->round($DIGS+1), "\n";
print (   ($good - $pi), "\n");

#####################
# part 2
# (e^pi - pi) = 20 - delta
print " (e^pi - pi) = 20 ?\n";
$pi=$PI->copy();
# my $e = (new Math::BigFloat '10')->bpow((new Math::BigFloat 1)/(new Math::BigFloat $LOG_10));
my $E = new Math::BigFloat '2.71828_18284_59045_23536';
my $VENTE=new Math::BigFloat '20.0';
print "$VENTE \n";
my $diff = $E->copy()->bpow($PI)->bsub($PI);
print $diff->round($DIGS)," \n";
print " ",(($VENTE - $diff)->round(3)), "\n";

# some accurate pi to compare output to:
__DATA__
3.141592653589793238462643383279502884197169399375105820974944592 30781640628621