Zombie Door


Zombies are pretty cool.  This post describes something a little less cool, but uses zombies to explain the concept (in a shallow, transparent attempt to capture your attention!)

Zombie Door Method

Imagine we want to generate a uniformly distributed random sampling in some complex space that our random number generator does not directly support.

Let me start with an simple example.  Imagine we have a random number generator that produces a random integer between 1 and 100.  However, we actually want to generate random numbers between 41 and 50.  (I know there are better ways to do this, but …
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Failure is not fatal

This post is penned during a moment of extreme frustration, beware!

Kobayashi Maru


One of the reasons I loved the original Star Trek series is because no matter what the odds, no matter how hopeless the circumstances, no matter how impossible the foe, Captain Kirk always found a way to think his way out of the mess.  He never ultimately failed or lost to an opponent, not once, not ever.  That makes a great hero and fun TV!  Fictional super heroes do things that normal human beings could never possibly do … like fly, or be stronger than steel, …
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Coding and Complexity

Norris Numbers

I recently stumbled on the following article about “Norris numbers”


The quick summary is that for an untrained programmer, 1500 lines of code is about where they hit the wall before they succumb to complexity and organizational issues.  The next big barrier is 20,000 lines of code for those that have some training and a bit of experience.  The next big barriers are at 200,000 lines, 2 million lines, etc.  At each level, a programmer or team has to develop new techniques and strategies to overcome the inherent cognitive limits of our human brains.


Linux offers …
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Cutting the Cord

Update: 10/01/2014

Things just aren’t quite falling into place perfectly for this cord cutter.  Since cancelling our satellite, I’ve been monitoring 4 possible antenna DVR options.

  1. Tivo Roamio OTA.  This seems like exactly what I’m hoping for.  Maybe a little expensive on the monthly subscription, but I’m willing to give it a try.  The downside: not available anywhere, any target date has been scrubbed.  Rumors suggest best buy is removing all tivo products from their stores.  Oof dah.
  2. Tivo Roamio.  This is $110 more than the Tivo Roamio OTA for the initial purchase with the same monthly subscription.   On the

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Build Your Own PC (2014 Edition)

The World is Constantly Changing

The last time I built up my own PC was March, 2011 – going on 3 years ago.  The basic idea of building your PC and the basic skill set required are still pretty much the same, but a couple new things caught me off guard.  Because I only do this every 2-3 years, I don’t keep track of trends and buzzwords and product nicknames, so plowing my way through this is a bit of a (fun) adventure each time!

Basic Skills Required


  • For me, the most important requirement is necessity.  I typically am interested

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“fedup” with Fedora!

Fedora 18 “Spherical Cow”


I think everyone has a bit of a love/hate relationship with their technology.  We hate it when it doesn’t work, or we can’t figure something out, or something breaks or doesn’t make sense.  But we love the new upgrade, the fancy new desktop background, animated menus, or what have you.  Fedora 18 was just recently released so of course I had to jump on that and get all the new stuff here as quickly as possible.  Is it great?!?  Was it worth the wait?  Is it a waste of time?  Do I love it?  Do I …
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Setting up “autologin” on a gumstix running the 3.5 kernel (yocto, poky, et. al.)

The gumstix.org wiki has a page on how to configure your gumstix to auto-login on boot.  This can be very nice for “production” systems where the intention is to power on and run some specific firmware/code every time.

However, with the new Yocto/Poky images based on the 3.5 kernel, things have changed and the old instructions no longer work.  Here is a quick recipe to get autologin running again on the newer systems.  First of all credit to http://fedoraproject.org/wiki/Systemd for their section on setting up autologin on a virtual terminal with the new systemd architecture.

Step #1:

Compile this “autologin.c” …
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Android Tablets

What is the ultimate computing device?

Recently I just jumped into the world of tablets and wanted to share a few thoughts.

If we could build the ultimate computer, what would it look like?  Size?  Weight?  Battery life?  Transportability?  Network/Wireless speed?  Wireless access?  CPU Power?  Memory?  Hard drive space?  Graphics?  Display size?  Touch screen?  Keyboard/Mouse?  Voice input?  Cost?

The reality of today is that nothing meets all the objectives and gives us the ultimate in computing power, large display size, fast network speeds, comfortable typing and viewing, long long battery life, while slipping into our shirt pocket for storage and …
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Seat of the Pants Engineering: I Need More Power!

One of the challenges of bread boarding is finding the right voltage sources and ground pins to power and connect a variety of components.  Recently I was faced with the challenge of connecting a Gumstix Overo with 1.8V TTL signals to a VectorNav VN-100T IMU with 3.3V TTL signals via SPI.  I just happened to have 2 Sparkfun logic level converters on hand.

The gumstix overo is powered from a wall power supply.  The vn-100t needs 3.3v power and ground.  The two logic level converters each need a 3.3v power line and a 1.8v power line (high and low voltage) …
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Oh no! Fedora 16!

Day 1

Fedora 16 hit the streets on Tuesday of this week.  (November 8, 2011).

I immediately rushed out to do a test upgrade on one of my old PC’s running Fedora 15.  Initially I used preupgrade to do it all via download, but I was met with the above screen when the machine booted.  This was what I got when I should have seen a login prompt.  Some people see this after they log in and that probably indicates other issues.

This is not a very informative message!  I googled quite a bit, examined the logs in /var/log/gdm/ and …
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