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How many flies are in my apartment?

saml98.github.io

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Re: How many flies are in my apartment?

#91

Post by laputan_machine »

mig39 wrote: post #89

Really interesting work. I love the different models of how a fly moves around. This jumped out at me, though: >If we take a look at the animation now, we can see the flies look slightly more realistic (if not still a bit spazzy) Is "spazzy" a word that's used in different regional dialects of English as a term to just mean jittery? In most of the places I've lived, it's an offensive word.

Uh oh, sounds like they need to be sent to the gulags for re-education, then. Report the site to GitHub and I'm sure they'll scrub this horrifying prose.

Re: How many flies are in my apartment?

#92

Post by stavros »

TeMPOraL wrote: post #38
stavros wrote: post #28

Earlier quoted context omitted.

Okay, first of all, tell me more about this flamethrower. Also, when you say "nets", do you mean "screens", ie on the windows?

> Okay, first of all, tell me more about this flamethrower. Just a lighter, a spray can, and steady hands. I know you're probably disappointed, but simplest solutions do work best :). (To be absolutely clear: I only use this against wasps and hornets, and only in situations where there's no safe way of shooing them back out through a window.) Operation: hold the lighter in front of you, light the flame, spray above i…

takes notes furiously

Re: How many flies are in my apartment?

#93

Post by mig39 »

laputan_machine wrote: post #91
mig39 wrote: post #89

Really interesting work. I love the different models of how a fly moves around. This jumped out at me, though: >If we take a look at the animation now, we can see the flies look slightly more realistic (if not still a bit spazzy) Is "spazzy" a word that's used in different regional dialects of English as a term to just mean jittery? In most of the places I've lived, it's an offensive word.

Uh oh, sounds like they need to be sent to the gulags for re-education, then. Report the site to GitHub and I'm sure they'll scrub this horrifying prose.

huh? It was a legit question. I've lived in a lot of places with different dialects of English. Where a term in one place is seen as harmless, but means something completely different in another.

In this case, I've never heard "spazzy" used other than as an offensive term.

Your reaction seems more Reddit than HN, though. So you have that going for you.

Re: How many flies are in my apartment?

#94

Post by sp332 »

mig39 wrote: post #89

Really interesting work. I love the different models of how a fly moves around. This jumped out at me, though: >If we take a look at the animation now, we can see the flies look slightly more realistic (if not still a bit spazzy) Is "spazzy" a word that's used in different regional dialects of English as a term to just mean jittery? In most of the places I've lived, it's an offensive word.

I remember thinking that the UK has a much more negative connotation for "spastic" than the US. In the US it's still pejorative but something you could say casually.

Re: How many flies are in my apartment?

#95

Post by rossdavidh »

lolc wrote: post #34

All these models ignore how insects actually zero in on a smell. For a fly outside, the source of the smell is the gap in the window. What looks like random direction changes is actually a search pattern for that source.

There is presumably also a falling-off of the signal with distance. Flies may have a good sense of smell and all, but it's not infinitely good. Which is too bad, because if they did, then all the flies in NYC (or I suppose maybe the world) would all be in one big clump near the best (to a fly) smelling object. Although I guess if you were that object, then it would be not as good.

Re: How many flies are in my apartment?

#96

Post by anyonecancode »

aetherspawn wrote: post #37
mschuster91 wrote: post #10

Earlier quoted context omitted.

Flies are small... you'd need a lot of light, multiple angles and good cameras/lenses to decently illuminate the flies, which has the problem that all the light will only attract more flies.

I think it would be fine if you tracked only the flies that entered or exited through the small hole in the wall, ie not tracking the whole room just a tiny corridor. So yes, you know the delta-fly(er) but not the number of flies.

And if there were a small door over the hole, that opened only to allow fast moving flies to go through it from one direction and slow moving flies to go through it in the other...

Re: How many flies are in my apartment?

#97

Post by rossdavidh »

mig39 wrote: post #89

Really interesting work. I love the different models of how a fly moves around. This jumped out at me, though: >If we take a look at the animation now, we can see the flies look slightly more realistic (if not still a bit spazzy) Is "spazzy" a word that's used in different regional dialects of English as a term to just mean jittery? In most of the places I've lived, it's an offensive word.

"Spazzy" or "spastic" is not especially offensive in the US, although I suppose given our ever-escalating sensitivity it soon will be. It mostly just implies "given to spasms", which I suppose is the origin. More generally, it implies not terribly well-organized in behavior. A person might say it of their own behavior without meaning anything exceptionally bad.

Re: How many flies are in my apartment?

#98

Post by mjaniczek »

m12k wrote: post #40

In my statistics class we were taught a technique for estimating the number of flies in a barn. You capture a fixed size sample of flies, e.g. 100, and give them each a little white dot on the back, then release them all back in the barn. Leave them to mingle for a while, then capture another fixed number of flies, e.g. 100. If 5 of them have a white dot on them, then you estimate that the 100 flies you captured orig…

I wonder how does that work. Why can you use the 5 flies you found to divide the total sample size?

It's kind of giving you an invariant number: * 100 flies -> 5 flies (5%), 100 / 0,05 = 2000 * 80 flies -> 4 flies (5%), 80 / 0,04 (not 0,05) = 2000

But if you used the percent instead (which seems to be what you hinted at) then the results vary: * 100 flies -> 5 flies (5%), 100 / 0,05 = 2000 * 80 flies -> 4 flies (5%), 80 / 0,05 = 1600

What's the principle, does it have a name I could read more about on Mathworld / Wiki?

Re: How many flies are in my apartment?

#99

Post by vagrantJin »

m12k wrote: post #80
Aeolun wrote: post #76

Earlier quoted context omitted.

I found two flies in my house, marked them, then later found two more flies without marks. I think this means the population of flies in my house is infinite.

My condolences, that doesn't sound very nice. Unless you're a frog, in which case, congratulations!

Dear m12k,

I have a valid reason to outlaw humour.

Because of you comment 3 things have happened.

1) I snorted, causing my hot tea to use my nostrils as an emergency exit.

2) My nose became a tea tap.

3) My screen and keyboard, bless them, are covered with tea. My shame in cleaning it up is indescribable.

Bravo.

Re: How many flies are in my apartment?

#100

Post by Tempest1981 »

0xBA5ED wrote: post #83

A tip if you have an annoying fly in your house that's hard to swat. Turn off all the lights except the bathroom. In a few minutes it'll fly in. Close the door and it's mano-a-mano.

Also works with a computer display in a dark room. Until you hit the display going mano-a-mano.
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