bohnsack.com

I'm registered for this year's Tour de Kota:

Sunday, June 11th through Friday, June 16th - Yankton to Milbank (462 miles).

Yesterday I proposed marriage to Elisa, during a nice walk in the mountains at Doc Long Picnic Ground. Thankfully, she accepted (she blogs about it here).

It was a beautiful day in Albuquerque and the East Mountains – almost spring, with just hint of chill in the air. The mountains were peaceful and restorative, after many weeks of stress at work and school. The festive sounds of a picnicking family and their excited Spanish conversation greeted us at the entrance, but after only a short walk into the forest, it was only us, the wind through the trees, and the rest of nature's majesty. Near the end of our journey up the mountain, we scrambled up a steep bank onto a sunlit trail, walked some more, and I knew it was go time...

We stopped at an especially well framed portion of the trail. I knelt and then very emotionally proposed. She said, "Really!?", I replied "Damn Right!", she said, "Yes.", and all the world's chaos was transformed into a system of two, two-variable linear equations. Great mysteries became intuitively obvious, and jigsaw puzzles solved themselves spontaneously.

After it was done, we walked a bit more and came to sit on some large rocks that overlook the highway, as it snakes up to Sandia peak. We talked about our future together and said to ourselves, while watching people motor up the mountain, "Look at us way up here in the mountain, and look at you down there oblivious to us and our happiness." It was goodness of the highest order.

Never, ever, did I anticipate being lucky enough to find someone so beautiful, intelligent, determined, grounded, curious, loving, supportive, and just plain wonderful to share my life with. Well... I have. I love her unconditionally, she loves me back, we're going to be married, and I couldn't be happier.

We've yet to make any decisions on dates or make any specific plans.

One of the most useful CSS resources I've run across.

The first programming assignment for my parallel processing class is an implementation of the Sieve of Eratosthenes with MPI on a parallel machine.

Fun!

References:

• http://www.amazon.com/gp/product/0072822562/
• http://parlweb.parl.clemson.edu/~walt/ece493/ece493-4.pdf
• http://www.cs.hku.hk/linux-workshop/workshop01/prime.htm
• http://users.cs.dal.ca/~arc/teaching/CSci6702/2004/Assignment1.htm
• http://www.thenearside.net/casey/documents/CMorford-CZeh_ECE5504.pdf

The serial algorithm in Ruby:

#!/usr/bin/ruby -w
max = Integer(ARGV.shift || 100)
	
sieve = [nil, nil] + (2 .. max).to_a
	
(2 .. Math.sqrt(max)).each do |i|
  next unless sieve[i]
  (i*i).step(max, i) do |j|
    sieve[j] = nil
  end
end
	
puts sieve.compact.join(", ")

When I was in France, I saw a road sign that said something like 1,432 km to city XYZ. I quickly turned to my travel companions and exclaimed: "Look, 1.432 megameters to city XYZ!".

It seemed like a perfectly valid (and possibly slightly clever) observation to me, but as I recall, everyone looked at me very strangely.

Click on the shirt to go to my CafePress store, where you can buy this and other similarly beautiful items displaying the famous VAPI_RETRY_EXC_ERR message:

I've had a collection of unread LaTeX texts on my bookshelf for a damn log time. What... ten years?

This semester however, I buckled down and started using it (TeX not the books) for classwork. i.e., I got it done. The first showing is my submission for CS 481 Homework #1. You can check it out here.

It turned out pretty smooth. The diagrams are a little weak, but TeX has the power, and I'll get similar diagrams done beautifully, the next time I have the opportunity to play with all the possibilities.

One interesting thing about the experiment is that I found myself having no need for any of those crusty reference books. Today's Internet, Google, and other people's example markup was all I needed to get it done. Sweet!

bohnsack_cs481_s2006_hw01.pdf

Specific instruction #6 for CS 481 Project #1: "Avoid memory leaks in your program."

Valgrind to the rescue...

Before:

==31405== ERROR SUMMARY: 720 errors from 2 contexts (suppressed: 11 from 1)
==31405==
...
==31405== malloc/free: in use at exit: 17,280 bytes in 720 blocks.
==31405== malloc/free: 5,770 allocs, 5,050 frees, 54,595 bytes allocated.
...
==31405== LEAK SUMMARY:
==31405==    definitely lost: 17,280 bytes in 720 blocks.
==31405==      possibly lost: 0 bytes in 0 blocks.
==31405==    still reachable: 0 bytes in 0 blocks.
==31405==         suppressed: 0 bytes in 0 blocks.

After:

==7634== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 11 from 1)
==7634== No malloc'd blocks -- no leaks are possible.

Ahhhhh... Bye bye memory leaks.

Iowa State gets a Blue Gene/L - 2,048 processors with a peak of 5.7 teraflops. Not too shabby.