Technical Difficulties from on Top of the Mountain
2006-04-26
  Visitors in the house
Its been my practise to keep cats around the house (or at least outside), but our last set ran off at the end of summer and we haven't gotten new ones yet.

What we did get was a visitor this week. Luckily our house is pretty devoid of food and water, so the mouse was not very fast and was caught with a piece of cardboard and a tupperware container. Not the evenest of matchups.

Turned the mouse outdoors so the hawks can have a snack. I let nature do my dirty work.

 
2006-04-23
  Arriving at the answer as easily as possible
I was in a lot of competitions back in my school days. There really wasn't a lot else to do. I didn't really study, and the teachers figured they better keep me busy or I'd just cause more trouble that I was already doing. So I got sent off to win trophies. There were math competitions, orchestra competitions, physics competitions, engineering competitions, drafting competitions, science competitions, accounting competitions; I even got sent off to a spelling bee once (by mistake probably, I hate spelling). But one of my favor ates was the computer competitions.

The first reason I liked computer competitions was that the school, or some local business (back when local businesses sold computers), would loan me a computer for a couple of weeks to "get ready". Actually I'd spend every night writing and playing games on them. (Back then a computer cost more than a car, so my parents had not bought me a computer of my own.) My parents didn't know what I was doing on the thing, and maybe writing games could be considered "getting ready" in any case. The second reason I liked computer competitions the best was that I liked writing programs under pressure even better than normal, as I considered myself rather good at thinking under fire, and whipping out five or six solutions in a couple of hours by myself just left those other teams of three and four people in the dust.

Interestingly enough, I often missed problems or could not come up with a solution in the time allotted. Luckily, no body else could either, but I learned from those problems, especially in competitions where they handed out the answers afterwards.

On particular problem was called magic squares. Basically you had to generate all the possible permutations of valid magic squares for a grid of size N. I of course tried to write something that would automatically permeate the board through its valid values: put a 1 in the first square, then create a list of numbers remaining and use that to populate the adjacent nodes and so on and so on. A big complicated mess of permutation trees. And I was trying to do this in BASIC on a 6502 machine. In about 20 minutes. Needless to say, I didn't succeed.

The answer turned out to be far more simple. Create a square NxN filled with the number 1. Then start adding 1 to the first square, carrying forward when it wrapped beyond N. Sure this generates a lot of invalid answers, but you just test to see if its valid at the end of the day, and only print it if it is. Wow, let the computer do all the hard work generating thousands and thousands of wrong answers and only bother to say something if it happens to find one that's right. "Brilliant!" I thought.

Computer back then could handle millions of cycles per second and thousands of pieces of information with ease. Who cares if you send them down dead ends again and again. (Besides Marvin the paranoid android) This approach turns out to be even smarter when you want an answer that's good enough, but you don't care how good enough it is. I ran into just this situation a few years later.

We were living in California and the S&L crisis had just passed which meant there were a lot of banks around with the name "Federal" in them (as in the federal government had bailed the banks out and now basically owned them). I was banking at Fidelity Federal and had my checking account, business account and mortgage there. (Its convenient to apply for a mortgage from the same back where your checking account is--when they want to know your account balance and last six months history, you can tell them to go look it up themselves.) Anyways, out of boredom I had started reducing the fractions on my checks sometimes. Like 50/100 is the same as 1/2, and in fact back in sixth grade if you wrote down 4/8 for an answer instead of 1/2, you were likely to get marked off by the teacher--it wasn't proper. So I started writing amounts like 19/25 on my checks. Then I noticed something even stranger.

SIDENOTE (for those under 30) Once apon a time the world did not run on plastic & electrons. It ran on paper. Specifically little rectangular pieces of paper, a little smaller than money, called checks. They came from the printer in little books, and we'd carry one around with us everywhere and called them "checkbooks", and they had your name & address on them and a little number on the corner which went up on each successive page. The first one was 101, then 102, etc. Actually, a check with '101' on it made you look like a newbie, so if you were really hip, you ordered your first book of checks (for your checkbook) starting with 501 or something. Then you looked really cool. And then the really bizarre part was that after you wrote a check and gave it to the store, and then the store sent it to your bank to exchange for dollars, and the bank took the money out of your account; it saved up all these little scraps of paper and sent them back to your at the end of the month. I know, you're thinking crazy, but that's what they did.

Anyways, one day I was looking at the checks that came back from the bank (ok, must have been a really slow day), and I noticed that somebody had taken the check that I wrote for eighteen dollars and 19/25ths, and had entered 19/25ths into their adding machine to verify that it came out to 0.76 and had noted on the check that it was indeed 0.76 and they had initialed it. I couldn't think of one possible reason why you would do that, but for some reason I decided that it was my mission in life to keep that guy employed, by writing every check from that day on as an odd fraction. Now even numbers were easy enough to reduce, I could divide any number between 2 and 98 by 2 easily enough, but the odd numbers were a little trickier. You can't really reduce 33/100 exactly. But then I had a wild idea. Maybe I didn't need too. Maybe I only needed to get close (like say 0.005 close). 1/3 was 0.3333333, but it rounded down to 0.33. That ought to keep that poor accountant busy for hours. Now I just needed some way to come up with the right fraction that was close enough for any decimal amount.

The solution turned out to be simple. Let the computer try a hundred numbers that didn't work and then have it stop when it found one that did. I told it to start with 0 / 1, adding one to the top if it was too small and one to the bottom if it was too big. No finesse, no optimizations; just brute force. For 0.33 it would just try 0/1, 1/1, 1/2, and then hit 1/3. For something a little harder, like 0.37 it would try: 1/1, 1/2, 1/3, 2/3, 2/4, 2/5, 2/6, 3/6, 3/7, 3/8, 3/9, 4/9, 4/10, 4/11, 5/11, 5/12, 5/13, 5/14, 6/14, 6/15, 6/16, 6/17, 7/17, 7/18 and then finally get 7/19 (which is 0.368421). Notice how it runs over the same ground a lot, like 1/2 2/4 3/6 or 2/5 4/10, but who cares. The core routine is three lines long:

dtmp= 1. * ia / ib, delt= dtarget - dtmp ; if ((-0.005 < delt) && (delt < 0.005)) break ; /** found it */ if (delt < 0.) { ib ++ ; } else { ia ++ ; } /** work closer */
Eventually I souped it up a little, adding another test to capture the results within both 0.005 and 0.001 (just for some variety), and I also made a wrapper that would call that function for all values between 0.01 and 0.99 so that I could make a little cheat sheet to carry around in my checkbook and use when I was at the store and needed to pay with a check.

Don't get a chance to use that routine much anymore these days. Press a button, pay the bill. Occasionally you might see someone in the checkout line writ ting a small novel in order to pay for two gallons of milk and a bunch of bananas, but the check book is pretty much extinct. Too bad, I kind of miss that guy in accounting.

 
2006-04-19
  Words of wisdom from the lunch table.
Hanging out with friends at the lunch table, they arrived at this bit of wisdom.
"Catsup is the duct tape of condements."

-- Willy W.

Sounds yummy. Maybe I'll stick to mustard.
 
2006-04-14
  How to use up an entire airline flight, and then some.
Regular sudoku is pretty easy once you know a handful of rules to narrow down positions. I try to do the medium & hard ones without any pencil marks, but the extra hard I usually use pencil marks on. Still, I seldom take more than 30 minutes to do one.

samuri sudoku

This thing on the other hand took me hours. You spend a lot of time chasing down dead ends. Not sure I need that kind of aggravation on a regular basis. Maybe I'll just go back to the normal ones.

 
2006-04-13
  Random connections
I don't think anyone actually reads my blog, except a few friends of mine. What's curious is how many people end up here accidentally. There they were, searching for something harmless, and poof, I end up being in the top ten results just out of pure coincidence.

Its really not my fault. I didn't set out to be the #1 results in google images for Maxstar 140, in the top 20 for dead hp kayak or the #3 results on the web for technical difficulties. It just sort of happened. And I've written about so many different things, that I end up with a lot of people bumping into old stuff I've written.

Just this week, I got a comment from The Modern Machinist who has a quite interesting site, at least I think its interesting. Its all in Russian, and thanks to his address starting with '-', babelfish can't load the page and translate it for me.

It does have some interesting images though. Kind of russian mythology crossed with a bit of Miyazaki.

 
2006-04-12
  Getting past technology
I really like my JVC camera, even more so now that 4GB SD cards are only $129 and 8gb compact flash hard drives are $150, but as I gather up directories of clips and face the finite limits of my hard drive, I'm frustrated by the proprietary format the files are created in.

Actually its not strictly proprietary, its a MOD file which at least a handful of different companies and software programs know about. One of which is Power DVD which came with the camera. While I guess I could install Power DVD on every computer I might want to watch my clips on, I was thinking there had to be a better way.

It occured to me tonight that the camera didn't come with any Mac software, and there had to be at least one mac user out there that bought this camera and then tried to read the files that it created. So I pulled out my handy internet indexing tool and entered jvc mc500 mac. The results for the first entry were very promising:

As a Mac user I was initially disconcerted to find that the MC-500 had no Mac oriented software at all.
None. Zero. Zip. Nada.
Ahah. This person obviously found the solution, and indeed he had: Squared 5 MPEG Streamclip. Crossing my fingers, I went to the web site and discovered there were converters to decode or re-code those crazy MOD files for both Mac OSX and Windows XP. So I downloaded the PC version, ripped out all traces of Quicktime, loaded the referenced KL Quicktime Alternative and loaded my first clip. Seconds later I had saved out the file as a normal MPG file and now can read the files without any trouble in Windows Media Player and VLC. They're even a little smaller.


Click for 4MB MPEG file

Obviously the best solution would be if the camera output normal files in the first place, but this will do as a workaround until someone comes out with an affordable HDV solid state 3-chip videocamera.

 
2006-04-07
  In the news.
I'm currently working for a company called IMMI that is a big secret, but we did just get /.'d. A lot of the commentors are so clueless its hillarious. "Why would anyone use a cellphone that monitors your music and tv listening habits?" How about because you get a free cellphone and free cellphone service? Heck, even I'll wear T-shirts with company logos on them if they give them to me for free. Though that's perhaps more because I'd be rather be spending my time at trade shows instead of department stores.
 
2006-04-05
  It just doesn't get any funnier than real life
The wife is sniffing the air and complaining:

"What's that smell."
"It smells awful, like skunks."
...
"Oh, its my cooking."

Note: It didn't taste nearly as bad as it smelled.

 
2006-04-02
 
Well March is past finally. We used a lot of wood, and a fare number of pellets. Not as much as previous months, but still pretty heavy usage, as it was snowing right up until the end of the month.

Here's the usage at this point:

November  1,200
December1,720
January2,000
February1,280
March1,080
April...

Its still freezing at night, but the wood stove seems to keep up with it most of the time. The basement itself is getting cold though, and so I continue to run the stove just to keep my workarea warm enough. Home Depot and Walmart both have more pellets in stock at this point, so I should be fine if I decide to top off the last of my reserves.

The big success was keeping the propane heat from coming on for most of the entire month. I think it came on twice. I haven't gone out in the mud and checked the tank, but I have great hopes that we've used very little of it. Given the price of propane these days, that would be a big help.

 
Life in the middle of nowhere, remote programming to try and support it, startups, children, and some tinkering when I get a chance.

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Blogroll
Paul Graham's Essays
You may not want to write in Lisp, but his advise on software, life and business is always worth listening to.
How to save the world
Dave Pollard working on changing the world .. one partially baked idea at a time.
SnowDeal
Eric Snowdeal IV - born 15 weeks too soon, now living a normal baby life.
Land and Hold Short
The life of a pilot.

The best of?
Jan '04
The second best villain of all times.

Feb '04
Oops I dropped by satellite.
New Jets create excitement in the air.
The audience is not listening.

Mar '04
Neat chemicals you don't want to mess with.
The Lack of Practise Effect

Apr '04
Scramjets take to the air
Doing dangerous things in the fire.
The Real Way to get a job

May '04
Checking out cool tools (with the kids)
A master geek (Ink Tank flashback)
How to play with your kids

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