The Accountant

The Accountant Official Trailer #1 (2016) - Ben Affleck Movie HD
I've been working on a programming problem / puzzle over at Codingame the last couple of weeks. The puzzle is called The Accountant, and it looks like they've managed a marketing tie-in with the movie. I mean, I hadn't heard of the movie until I started working on the puzzle.

The puzzle involves developing a search & destroy algorithm for Ben, excuse me, Wolff, to use to eliminate all enemy combatants without getting killed himself. As with many puzzles at Codingame there are several test cases. They start out relatively simple and easy to solve, but they get progressively more complex and correspondingly more difficult to survive.

I'm guesstimating that I only spent about eight hours actually working on my program, that is, actually sitting down at the keyboard and typing, but I spent untold hours thinking about it, and who knows how many CPU cycles my subconscious spent ruminating on it.

My first pass at the problem involved simple locating the closest bad guy and issuing a SHOOT command. That worked for about the first third of the tests, but now we have more bad guys and sometimes you need to run away for a bit to get some breathing room. Fortunately, actor (my name for the variable representing actor Ben Affleck's position on the field) can run twice as fast as the bad guys. Not surprising since he is a strong, physically fit American who is totally focused on his mission. These qualities are missing from the typical bad guy, at least in Hollywood, and likewise in this computer simulation of Hollywood.

But where do you run to? How do you figure out which area is safest? Well, you could use brute force, and simply calculate the distance from every point on the map to every enemy agent. But that could get expensive in terms of time and CPU cycles. There are roughly 150 million locations on our field and there could be a zillion enemy agents. You run a calculation like that and you could get shot while waiting for the computation to finish. Actually, the master computer would simply cancel you and your program because you exceeded your allocated time.

Computers have gotten much faster than when I first ran into that time limit thing. It could be that the master computer could actually make all those calculations in the allotted time, especially since there never any more than 100 bad guys on the field at any one time.

My early training in Computer Science instilled in me a desire to minimize CPU cycles, so I spent some time thinking about ways to reduce this HUGE problem into something manageable, trying to come up with strategies for mapping concentrations of bad guys and open, safe areas, and then trying to come up with a way to represent these ideas. I never came up with one I liked, which means that they all looked like a great deal of work. And there is no way of telling whether they would work or not without actually writing the code and trying them.

In the end I decided on a simplified brute force solution. I used the eight cardinal compass directions to locate eight points 1000 feet away (which is how far Ben can run in one turn, which I figure is about two minutes in real time), and then computed the distance from each of these points to each of the enemy agents. That brings the problem down from 15 billion computations to 800. And that was enough to pass all the tests.

Sark and the Master Control Program from Tron

I'm sure there are whiz kids out there who have developed very elaborate strategies for optimizing their total scores, but I'm lazy. I got the job done with simplest means I could find. Maybe I'll get a T-shirt, though if the master computer over at Codingame gets wind of this post, that will probably get canceled as well.

de Havilland DH.89 Dragon Rapide

DH89A RAPIDE Dave Marshall

The de Havilland DH.89 Dragon Rapide was a 1930s British short-haul biplane airliner for 6–8 passengers. It proved an economical and durable craft, despite its relatively primitive plywood construction. - Wikipedia

Michoud Assembly Facility

NASA - Liquid Oxygen Tank - LOX/GWT Tool. Time Lapse Video.
NASA is charging ahead with the construction of their SLS (Space Launch System) rocket booster. It's a sizable construction project and in order to build the rocket they needed to build some tools. The video shows the erection of two specialized welding tools in the Enhanced Robotic Weld Tool. The two hemispherical scaffolding-like structures are the tools. The one on the left is the Gore Weld Tool and the one on the right is the Circumferential Dome Weld Tool.

They are using Friction Stir Welding to join the parts of the tanks. Stir welding is kind of weird in that it does not involve burning flammable gases or electrical arcs. It works with brute force, which kind of explains why they need such substantial jigs, which is essentially what these 'tools' are.

This is all being done in the Michoud Assembly Facility (MAF) in New Orleans, Louisiana.

MAF is one of the largest manufacturing plants in the world with 43 environmentally controlled acres under one roof, and it employs approximately 3,700 people. From 1961 to the end of the Apollo program in 1972 the site was utilized by Chrysler Corp to build the first stages of the Saturn I and Saturn IB, later joined by Boeing Corp to build the first stage of the Saturn Vs. From 1973 to 2010 it was used for the construction of the Space Shuttle's external fuel tanks by Martin Marietta Corp., Denver Colo.  

The facility was originally constructed in 1940 at the village of Michoud, Louisiana to make plywood C-76 cargo planes and landing craft. During the Korean War it made engines for Sherman and Patton tanks, and boasted a 5,500 foot paved runway. - Wikipedia

The Sagittarian - Illumination

The Sagittarian - Illumination
This song is one of my favorites. I posted a couple jet fighter videos that use this song as a soundtrack. One was two years ago, another four years ago.

After watching a zillion videos on YouTube, I've realized that there aren't very many that portray women as seductive. I would say 'sexy', but sexy these days seems to revolve around boobs and butts and most of the 'hot' videos out there are pretty boring and/or repulsive.

This one is exceptional. I especially like the girl on the cover. The dancing seems to be done in slow motion, which might be part of the appeal. It might be the costumes or the young, slim, female figures, but I think the big attraction is the motion. And in all my video watching I haven't seen anyone wearing a similar costume.

Mysterious Goings On

Mysterious Goings On
California Bob installed a security camera and right off the bat he caught a couple miscreants prowling his street.

Detroit Steve sent me this link:

So You Want To Learn Physics...

by Susan J. Fowler

She lays out a course of study that you can pursue on your own, mainly through reading and studying the listed books. That's fine, but there was one statement in her introduction that caught me crosswise:

"Remember that anyone can learn physics." 

Not true. Anyone might be able to learn physics if properly motivated, but that's not going to happen to everyone. You also need an ability to engage in logical thought. Aptitude and inclination can make it easier.

There are two kinds of people in this world: people people and things people, by which I mean some people are better at dealing with people and some people are better at dealing with things. Obviously there is some overlap, but I would venture to say that a person who would make a good social justice warrior, or politician, would probably not make a good physicist.

To Infinity and Beyond!

Buzz Lightyear

I subscribed to NASA's YouTube Channel in the hope they will send me something interesting. Mostly it's been astronauts talking about life in the space station, or videos of hurricanes. Chit-chat doesn't do much for me, and once you've seen one hurricane blanketing the Earth with a fluffy white blanket of clouds, you've pretty much seen them all. Today though, we got something a little different. I suspect the video is more front-men bloviating, but the blurb that accompanied it was enlightening.

An Oct. 11 opinion article written by President Barack Obama and published by CNN, outlined a vision for the future of space exploration. In it, the president echoed the words in his 2015 State of the Union address about the importance of sending humans on a roundtrip mission to Mars by the 2030s, and developing technology to help us stay on the Red Planet for an extended time. That same day in a blog post, NASA Administrator Charlie Bolden and John Holdren, assistant to the President for Science and Technology, discussed two NASA initiatives that build on the president’s vision and use public-private partnerships to enable humans to live and work in space in a sustainable way. The first was the selection of six companies to develop habitation systems as part of the agency’s Next Space Technologies for Exploration Partnerships or NextSTEP program, designed to lay the groundwork for deep space missions. And this fall as part of the second initiative, NASA will start the process of providing companies with a potential opportunity to add their own modules and other capabilities to the International Space Station. The move is in-line with NASA’s plan to support and foster the growing community of scientists and entrepreneurs conducting research and growing businesses in space. - NASA YouTube video.

Link to NASA's NextSTEP press release from last year.
Pergelator posts about Orion Spacecraft

I am a gearhead so I tend to focus on the spacecraft we will need for future missions to infinity. But to my mind, spacecraft are the easier problem. I mean it's all done with metal and numbers and physics and the tests necessary to prove their capabilities are pretty straight forward. Either it survived the trip into space, or it didn't. The harder problems are going to be sustaining a human crew for more than a few days, and how to keep them from killing each other. Compared to these kind of problems, building a spaceship is child's play. I only found one post on these difficult problems: HI-SEAS Mission

P.S. Had a hard time finding a picture of Buzz in space, and after I found this one I realized that he's using the Superman pose of holding his arms out in front on him. Hmm, symbolism.