Tuesday, March 31, 2015

Tuesday: Ok, I guess that'll be the third link, then.

Eh.  Close enough.
  • TWC should be nationalized, too.
  • The important thing is that he's doing what he enjoys.
  • I saw this story on twitter earlier, and ignored it since "heavy traffic" for me usually means it takes ten minutes to get home instead of 8.  This makes the rail plan make a lot more sense to me now though.  I assumed that the number of people who live in west Oahu and work in town was small, since having that long of a commute seems stupid.  The fact that having the zipper lane break, which I think only decreases the number of lanes by one, causes backups that persist so long shows that that's not true.  In addition, there seems to be only three ways to get from one side of the harbor to the other, with one of those being the long way around on H-2.  Therefore, adding a parallel rail connection seems like a reasonable solution.  In a similar future incident, even those people who drove to work could take the train home.

Monday, March 30, 2015

Monday: I hate Mondays.

My prism rainbow is moving across the room.  I should fit the motion as a function of time of day and wall/ceiling position.


Sunday, March 29, 2015

Sunday: It was indifferently rainy today, and I did nothing all day.

The tonkatsu with lunch curry was all wonky.

  • Owl.
  • I finally figured out why they keep talking to the Board of Water Supply about people getting stuck on trails.  They're in charge of managing the watersheds on the island, which includes the mountains.
  • Nice job trying to pretend to not be a dick while also having to pretend that you're not pretending that you're not a dick.

Friday, March 27, 2015

Friday: There were basically zero people at work today.

I ate the banh mi I got yesterday.  It was kind of soggy.

Thursday, March 26, 2015

Thursday: I had so much trouble at lunch today.

It's Prince Kuhio Day, so I had the fun random Thursday off, making this week and next a 4-1-1-2-4-3 pattern of work and off days.  

I then went to get lunch and had many small inconveniences that I was not expected.  I did get to stop at a red light on the way and make "black truck guy who is really in a big hurry to get somewhere, so he constantly switches lanes" angrily jerk his car into the next lane over because he really wanted me to run the light so he could too.  Then the light changed and he took forever to get his stupid truck up to speed, and then finally passed me to run two more lights before getting stuck at a red again.  Good job, truck guy.

In any case, I began ordering, and completely forgot the phrase "French onion soup."  I then couldn't find the part of the menu that contained the soups, so I had to wait for the person at the counter to remind me what soups exist.

Next up, this thing:
Do you see the problem?
You can tell at the straw-hole.  Somehow I got a lid that was actually two lids, but not just two separate lids.  The two were sealed together at the edge, and I couldn't figure out how to pull them apart.  Also:

These chairs.

Are clearly designed to kill people.  There's just enough of a back so that you think it's a real chair, so you can nearly tip over backwards.  

  • The news mentioned that the Hawaii film festival is coming up.  I went to check what movies they're showing, and as I scrolled through, my exact quote was, "Holy shit, 'When Marnie was There' is playing before the actual release!"
  • Lex Luthor.
  • Dogs aren't very smart.
  • Sun Noodle makes the ramen for the ramen place.








Wednesday, March 25, 2015

Wednesday: I get to sleep in tomorrow.

I have no idea what Kitty is supposed to be dressed as here.  Batman?  Generic Halloween?


Tuesday, March 24, 2015

Tuesday: You are doing that wrong. Stop doing that wrong.

I'll have to take a picture tomorrow, as this doesn't relate to anything.
Things I Saw People Doing Wrong Today:

  1. If you're going to turn left, you do not need to turn slightly right before you turn left.  This is true if you're turning right as well.  Roads are designed so any car with a reasonable turning radius can turn corners without hitting the curb.  You do not drive a semi-truck.  Your back tires will follow close behind your front tires.  When you swing out, everyone has to get out of the way so you don't hit them.
  2. I can not conceive of a situation in which moving your car from one parking spot in the garage to a different spot could possibly save you any time.  I have seen at least two people who live in my building and have two cars and two spots switching them around.  Why?  When is that going to help anything?
Links.


Sunday, March 22, 2015

Sunday: Ramen adventures.

Black tonkatsu.  No egg, because I don't like eggs.
This is next on my list of cataloging all the ramens.  Kotteri, umakara, spicy tan tan.  This isn't bad.  Char siu, menma, woodear mushrooms, the egg I didn't get, and black garlic oil in tonkatsu base.  Unfortunately, competing with kotteri and spicy tan tan isn't fair, so this is number three on the list.  Very garlicky, which makes it hard to finish all the broth.


I also had time this evening to finally sit down and code up a simulator to answer the question I keep having when I watch this Last Man on Earth show (which I don't think is very good, since half the cast play horrible people, and because I can use the phrase "half the cast" on a show with that title).  Given that one person survived whatever killed everyone, how likely is it that there's another person alive as well.  This is basically a Bernoulli trial problem, where we don't know k or p.  I'm taking N = 300e6, which is close enough to the population of the US.  The results:


Normalized to the probability that everybody died, with the curves ranging for logarithmically spaced p values from 10**-8.4 to 10**-7.8.

If you think you're the only one alive, then you estimate that lp = -8.4.  However, once you find out that another person is alive, then lp >= -8.3 is the minimum (in this resolution), and those two cases have similar probabilities.  If you assume that k = 2 is the most likely probability, this moves lp to -8.1, and you have strong evidence that a third and fourth survivors are also likely.  Finding the third again bumps things up, and you can start expecting up to 8.  A fourth?  You've reached the other end of the simulation, and although the dynamic range of probability ratios increases, it's not excessive.

Basically, once the guy found Kristen Schaal, he's no longer the last man on Earth, and the likelihood of finding a lot more people jumps.  I will say that his strategy of travelling around writing the city he's living in seems like a good idea, assuming he wrote on a sign there that he's still driving around looking for people if they don't meet him.  That way, people will stay there and wait instead of assuming it's empty as well.  If he did meet a city with survivors, he could just change that sign to redirect to survivor-town.


Saturday, March 21, 2015

Saturday: Another Burrito Adventure.

The first interesting thing that happened today was while I was trying to decide what to have for lunch.  I kept hearing a "whoop whoop" sound from outside, and after a few minutes, realized that one of the other apartment buildings had their fire alarm going off.
It's not mine, because we use bells.
I couldn't see any smoke, and it went off again about an hour ago, so something is broken somewhere.

In any case, I eventually decided to drive to Kailua to get a burrito, because that seemed like the best idea.
It wasn't as good as I remember, partially because I added guacamole, and that decreased the average temperature a lot.  Cool soggy burrito isn't the best.  They still need queso.
 I was further back in traffic when I took the matching shot:
And because the sky looked like this today.
I went to the Pali lookout on the way home.  That totally justified driving across the mountains to get a burrito that wasn't as good as I hoped it would be.
This is now my new most favorite sign ever.  Poor confused wind-swept bees.
 As you probably could guess, it was windy, and the clouds on the earlier photo:
Are pretty much right there.  
See?
 I still have no idea why all the stray animals in existence gravitate to the Pali outlook.
Chickens.

Stupid feral cats that people were trying to pose with.  You're an invasive species, cat.  You shouldn't live here.

And there was a rainbow when I got back to town.




Friday, March 20, 2015

Friday: Whatever, it's the weekend, I'll fix it next week.

Also it was rainy today.

Thursday, March 19, 2015

Thursday: Bird Party.

I don't usually have bird parties outside my office window.



Wednesday, March 18, 2015

Wednesday: Fuck.

Because we've only been talking about this project for a month, now is totally the best time to double the scale of it.

Sure.  Why not.

Tuesday, March 17, 2015

Tuesday: Yeah, kind of like that.

:) :| :(


Monday, March 16, 2015

Monday: There are always far too many things to do.

"Ha ha!  I'm smashing up your boat! Sucks to not fly, doesn't it?"




Sunday, March 15, 2015

Sunday: I've spent way too much time on this stupid problem.

So links go first.


Today's main point is a continuation of thoughts on Ewoks from six years ago.  Earlier this week, I saw this image in my RSS stuff:


And searching online for it again led me to this, which is an overly long discussion of a bunch of nonsense about how Endor would have been incinerated by the debris from the Death Star.  After thinking about it for a few minutes, I came to the conclusion that that didn't make much sense, as pre-explosion, the DS had to have been moving sufficiently to not crash, so after the explosion, only a small fraction should hit the planet.  Right?

So let's throw physics at the problem, and see.  According to the Star Wars wiki page, Endor has a radius of 2450km radius.  If it has the same average density as the Earth, this gives it a mass of 3.39e23 kg.  We're trying to slam stuff into it, however, so let's go with an alternate calculation that the surface gravity is the same as on Earth (the Earth density Endor has about half-Earth gravity).  This gives about twice the mass at 8.82e23 kg.

Now we know what the target looks like, but what about the DS?  It apparently has a radius of 80km.  What does that mean in terms of mass?  No idea.  It's made of "quadanium steel," so we have to make something up.  Is it steel?  That's 7.75 g/cm^3.  Maybe quadanium makes it lighter, so maybe something like aluminum at 2.70 g/cm^3?  Plus, a lot of the DS is empty, because otherwise you couldn't do stuff inside it.  So there's a fill factor to deal with.  Let's say all the rooms look like this one:

This one.
That's an imperial shuttle, and those are 20m long, and roughly square-ish.  Stamp that footprint around, and I come up with something like 120m * 120m * 60m = 864000 m^3.  If the walls are 5m thick, the fill factor for the DS made up of these rooms is 33%.  In the first movie, the walls tend to look thin like a regular wall.  This yields a fill factor of about 1%.  This results in less mass for the DS, which turns out to be super important.  The high end mass is steel with fill factor=1.0, or 1.66e19 kg.  The low end is aluminum with a 1% fill factor, at 5.8832e16 kg.

Why?  The DS blows up.  It's a good "kablooey" kind of explosion.  Assuming this is going to completely disperse all the mass to infinity, this means the explosion is comparable to the gravitational binding energy, U = 3/5 * GM^2 / R.  For our 80km radius, and the high and low mass estimates give binding energies of 1.38e23 and 1.73e18 MJ.  This has to be converted to kinetic energy of all the debris particles, so assuming equal mass, each particle gets, U = 1/2 (M/Np) * v^2, so v = sqrt(Np) * [129 7.67] km/s.

What's left to know?  Where the DS is located in association to Endor.  I remembered this scene:

Zap!
But that turns out to not help.  I had planned to measure the length of the chord on the arc of Endor, and use that to work out how far behind the DS it is.  However, since this is the CGI reconstruction of two models on a stage, this doesn't work.  Using that chord to work out the projected scale of Endor, given the known "real" radii of the two objects means that Endor is in front of the DS, as the model Endor wasn't big enough to create the correct arc.

This isn't a big deal, as I remembered that the DS is orbiting Endor because there's a shield generator that's protecting it.  This means the DS has to be in a geostationary orbit.  That wiki page for Endor claims it has a period of 18 hours.  So the DS orbits at 18433km, and has an orbital velocity of 1.79km/s (which was yesterday's plot).

Put this all together, and run it through the N-body simulator to see what happens, and you get:

It freaking explodes.
How much does it explode?  It explodes all the way.  For the randomly placed particles (they all start on the surface of the sphere at 80km), one triggered the "collision" flag in the simulation.  This makes sense, as at the distance to Endor, it subtends 0.13radians, which translates to 0.435% of the full sky close to the 1/200 simulation particles hitting.  This is still 2.94e14kg being dumped on the planet.  That's about a third the size of the Chicxulub impact, although it'd be spread out somewhat instead of being a single impact.

The other fun thing I tried was reducing the explosion strength by slowing the particle velocity:

Red is 100 times smaller and blue is a 1000.
In these cases, the particles continue to largely follow the original DS orbit.  In the lowest energy case, Endor is spared, and the extra energy goes to kicking particles out.



Saturday, March 14, 2015

Saturday: Ok. So it turns out that it's a bit harder to knock together an N-body simulator than I thought.

Especially when I dedicated "this episode of Wonder Woman" to it.  Plus I had a units issue with the gravitational constant, blah blah.  It's harder than a one or two hour project.
Not impossible, of course, as this 2-body simulation shows.
It also didn't help that I spent most of the day watching youtube and TV, and trying to figure out what I wanted for lunch.

Sushi turned out to be the answer.
I'd also waited so long that the mall was super busy, so parking was harder than usual.  There was also some mall event fuckery going on.
I have no clue what this picture is showing, which is why I called it a fuckery.

The line?
The mall is never a fun place to be when it's crowded.
  • Not yet.
I forgot that it's pi day, and the whole world is going crazy writing digits all over the place.  The only things you need to remember most of the time are the song (lyrics with translation):


And that if you need to use pi, most of the time you should just use 4.0 * atan2(1,1), because that's going to give you more precision that you probably need.



Friday, March 13, 2015

Friday: There was going to be a lot of math here so I could come up with an answer to a problem no one cares about.

But, I realized I had to take more measurements, and remember a geometry formula from long ago. I think there's a perspective thing to sort out as well.  And then I need to write an N-body solver, which is somewhat unfortunate.  If I really wanted to be correct, I'd make it do adaptive mesh solutions as well, as I suspect the particles would actually disperse more than a rigid body solver would handle.  Maybe I'll just run two resolutions and call it good.

Anyway, there's a lot of math I still have to finish before that's ready.  Plus I have to solve sports this weekend too.  It's going to be a busy weekend of silly math.

At least it's better than fighting the Robots of Bone Valley from the Planet of Permanent Eclipses.


Thursday, March 12, 2015

Thursday: "Wait, is that a fucking armonica?"

Yes.  Yes it was.  I'm driving home, flip to the classical station, and I'm immediately trying to figure out if the song is orchestrated for organ, or if that sound is an armonica.  It was a weird drive home.


Wednesday, March 11, 2015

Wednesday: I simply don't have a title for today.

"What?  This skeleton was totally like that when we got here and sat down."

Tuesday, March 10, 2015

Monday, March 9, 2015

Monday: That was a surprise

While I was working this afternoon, I looked up to see a rainbow on my office wall.
Not the one on the chalkboard.  That's not a real rainbow.
 Apparently today is the day that the sun shines perfectly on the prism I have on my windowsill.
Along with the important styrofoam block, break key, penny-under-plastic-cap, iron squirrel, and wooden owl.

Sunday, March 8, 2015

Sunday: I was disappointed with today's lunch, as well.

Today I wanted to get stuff at WF, and I kind of wanted a burger, so I went to the Counter.  Surprisingly, 3:30 on a Sunday is the busiest time there.  This meant I had to eat at the bar, which I don't like.

Also that one "oven roasted tomato" is all I got.  Similarly, that single tiny carrot thread was all I got of that.  WTF, burger jockeys?  You can't spare any extra veggies for my burger?  The Korean BBQ sauce is also not terribly good, as it doesn't have much more flavor than the sesame oil.  The sweet sriracha isn't very spicy, either.  It's not bad, but it's missing a lot of kick.

I also discovered that the mall has a good view of Diamond Head as well.  Between this and Safeway, it's entirely possible I could put together "36 views of Diamond Head."
This weekend was also the Honolulu Festival.

So fireworks.

Saturday, March 7, 2015

Saturday: It's a good thing I had leftovers to eat after that lunch disaster.

Guy: "HOLY FUCK, I'M OUT OF HERE!" Horse: "HOLY FUCK, AS IF I NEEDED MORE PROBLEMS!" Lion: "Honestly?  Even I'm confused as to how this all came about."

  • Looking over Raden Saleh's wikipedia page, it looks like this is not the only "lion noms on horse while they plunge off a cliff with a waterfall in the background."  How does that happen?
  • Red panda.
  • Service Pokemon.
  • Crows.
  • I bring my bags almost all the time now, so the bag ban won't really be a problem.
  • Ok, I know I really like my phone, but do other people really have phones so shitty?
    • 6: I have a thing in the pulldown config menu to lock the screen position.  Swipe swipe click.  Done.
    • 5: There's the ring volume and the media volume.  I have never had this problem.
    • 4: Ok.  Sometimes I type duck when I don't mean to.
    • 3: Never been an issue.  And when I need to click, I often get a little zoom in so I can clarify my click better.
    • 2: My phone knows when I'm looking at it, and keeps the screen on while I'm looking.  This is phone specific, so it just means my phone is cool.
    • 1: My battery lasts more than a day, and charges in less time than I've bothered to measure.

Shaloha is Sh-awful.

(15:47:41) me: hey

(15:47:50) me: remind me how hummus works
(15:48:39) Julie: Open mouth, insert hummus?
(15:49:07) me: just straight?
(15:49:17) Julie: Pita chips
(15:49:21) Julie: Carrrots
(15:49:29) Julie: Pita in not chip.form
(15:49:34) Julie: Tortilla chips
(15:49:46) me: ok. just so I'm not completely crazy
(15:49:49) Julie: Did you just have a stroke? How do you not know this?


No, I did not have a stroke.  I went to the most disappointing restaurant I've ever been to.  Last night, I saw the Food Wishes falafel video.  That led me to looking to see what middle eastern restaurants are in the area.  Yelp suggested Shaloha, which has lots of good reviews.  I would suggest that Yelp should stop letting stupid people rate places.

First off, the pictures suggest people eating at tables.  There are no tables.  There is no place to eat.  Not even "sit out on the sidewalk" tables.  The sidewalk was filled with racks.  So it's a take-out place, despite that not being evident anywhere.  This completely fucked up my "eat lunch, go to WF" plan.  There's no place in the neighborhood to really sit and eat, so I just came home.  I decided to get their shwarma combo, with falafel and hummus.

When I got home, I saw this:

Which led to the above conversation.  What am I going to do with a giant tub of hummus?  Eat it with a spoon?  You make fucking pitas.  Why would the hummus side not come with pitas?  You gave me a pita dipped in hummus when I got there, so you clearly understand the concept.  I'll ignore the fact that I thought hummus was supposed to be garlicky with some citrus hints from lemon juice.  This was kind of just gritty bland paste.  So why would you give out giant tubs of it with nothing to put it on?

I guess I could have put it on the falafel.
That probably would have helped tone down the dryness a bit.  These weren't awful, but they didn't really have much flavor, even with the hot sauce added.

And now the biggest "yeah, we're lying jerks."  Their webpage shows nice looking sandwiches, with the standard meat/veggies/tzatziki in a folded pita.  What did I find when I opened the foil on my sandwich?

A fucking gob of cabbage.
WTF?  That shows up in one picture, and it's a just a bit, not a giant cap?  Not surprisingly, everything inside tastes like shitty cabbage.  The chicken inside was dry and flavorless.  Yes, I just picked it out and chucked the rest, because I wasn't in the mood to eat a mess of vegetables drenched in cabbage juice.

And as you can see dripping at the bottom, oil.  From what?  It can't be the chicken.  That hadn't seen any liquid in years.

So bottom line, fuck this place.