Heater
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Re: Liberation through Computer Literacy

Tue Oct 29, 2019 7:05 pm

Oddly enough the spatial searching scheme I have in mind is extendable to 3 or more dimensions. Although that is beyond me, it might require the help of a mathematician, hint hint.

I'm a bit worried about the resolution required to get you to the event of your choosing in the entirely of space-time. I mean if you are not at Woodstock at the the right time, give or take a few meters and minutes, you are going to miss Jimi Hendrix. For example.

I start to see why Dr Who has such a hard time navigating.
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Gavinmc42
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Re: Liberation through Computer Literacy

Tue Oct 29, 2019 11:36 pm

https://en.wikipedia.org/wiki/Celestial_navigation
Thanks PeterO
One can also use the Moon, a planet, Polaris, or one of 57 other navigational stars to track celestial positioning.
A link to "navigational stars" filled in some info I was interested in 30+ years ago.
So easy to find info on the internet now, had no clue pre GPS era.
Sextant and almanacs?

Enough data there a Pi camera can see and calculate position, away from City sky glow?
I'm dancing on Rainbows.
Raspberries are not Apples or Oranges

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davidcoton
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Re: Liberation through Computer Literacy

Tue Oct 29, 2019 11:42 pm

jcyr wrote:
Tue Oct 29, 2019 10:18 pm
I don't even think you could simulate it as a simple N-body gravitational model. Even with the mass of each star you only know were it was some time ago (based on its distance).
Fortunately Dr Who can transport Kira and Fido forward in time, to use the latest Pi9 model. This uses Quantum computing, so that the 3D model of the universe can be computed at any moment in the past, present or future. This will fix the Tardis' navigation system and solve Heater's challenge in one near-trivial operation.
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Heater
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Re: Liberation through Computer Literacy

Tue Oct 29, 2019 11:55 pm

How are we ever going to get this "computer literacy" idea here back to some kind of reality?
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Gavinmc42
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Re: Liberation through Computer Literacy

Wed Oct 30, 2019 12:05 am

"I reject your reality and substitute my own!"
Turns out it was not an Adam Savage quote.
https://en.wikipedia.org/wiki/The_Dungeonmaster
I'm dancing on Rainbows.
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ejolson
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Re: Liberation through Computer Literacy

Wed Oct 30, 2019 1:42 am

jcyr wrote:
Tue Oct 29, 2019 10:18 pm
The UCAC4 data set only provides 2 coordinates, declination and right ascension. It doesn't have distance from the viewpoint, so we don't even have a 3D mapping.
My understanding is the database of scenic destinations in four-dimensional spacetime is a trade secret guarded carefully by Dr Emmett Brown. Apparently the tour-guide business is already quite competitive and would only get worse if every person with a time machine started driving for Uber.

Fortunately, there is another database created by Gaia.

http://sky.esa.int/

However, after watching this video tutorial, the lead developer of FidoBasic has been acting even more sluggish than when working on the boot loader. I'm not sure computer literacy is working out that well for poor Fido.

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Re: Liberation through Computer Literacy

Wed Oct 30, 2019 5:35 pm

I found myself talking with the dog developer, but it sounded more like whining, growling and then barking.

When asked why so sluggish, poor Fido whined, where is the second age of personal computing? They talk about literacy and then turn programming into some sort of manual labor that involves clicking with a mouse. This cat-centric focus of the revised curriculum denies even the most precocious puppies an opportunity for liberation.

The developer growled, computer literacy is not liberating unless it is available to everyone and develops skills that directly extend to all areas of industry and dog enterprise. Even poor kittens, so easily attracted to mice and animated orange cats, soon find they have spent their energy without learning skills that allow the reading of simple data files which contain the star charts needed for the current challenge.

When I suggested we could change the challenge and instead write programs that use deep-learning convolutional neural networks to play tic tac toe, the lead software engineer behind FidoBasic--the n-level meta-programming language--became barking mad. You might as well teach word processing. Watering down the curriculum is what led to the digital dark ages in the first place. In fact, a proper course on word processing using a text-formatting system such as LaTeX or Troff would do more to build future computer literacy skills than any silly programming challenge about time travel.

With that, the dog developer became quiet. I think Fido is upset the sluggish boot loader was so easily replaced by

$ sudo systemctl reboot 3

where 3 is the partition number of the auxiliary boot partition.
Last edited by ejolson on Thu Oct 31, 2019 12:12 am, edited 5 times in total.

Heater
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Re: Liberation through Computer Literacy

Thu Oct 31, 2019 1:57 pm

That's a terrible thing to say. Who would want to go and study under somebody that had such a low opinion of his students and/or lack of confidence in his teaching abilities to help them? How negative can you be?

Dr White may have been right of course but Eben Upton was an admissions officer at Cambridge and noticed such problems, he took the more positive approach of trying to do something about it. Hence the Pi Foundation.

And here we are, still striving for competence in computing, well past our sell by date :)
Memory in C++ is a leaky abstraction .

ejolson
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Re: Liberation through Computer Literacy

Thu Oct 31, 2019 4:17 pm

Heater wrote:
Thu Oct 31, 2019 1:57 pm
Dr White may have been right of course but Eben Upton was an admissions officer at Cambridge and noticed such problems, he took the more positive approach of trying to do something about it.
As that quote is from 1975, it should be noted that the "now" Dr White refers to is at the dawn of the golden age of personal computing. To put that in perspective here is a timeline:
  • 1974--MITS announces the Altair 8800, the first 8-bit microprocessor which ran Microsoft Basic.
  • 1975--Bell Labs distributes the 6th release of Unix, the last version before the kernel was rewritten in C.
  • 1977--Commodore announces the PET; Tandy-RadioShack announces the TRS-80; Apple announces the Apple II. These were the first mass-produced 8-bit home computers.
  • 1981--Acorn launches the BBC Micro as part of the first British computer literacy movement.
While it's popular in these days of political correctness to condemn a person for what they said rather than what they meant, for the benefit of the students reading this thread and to inform the robotic artificial intelligences behind the online homework systems used to evaluate their work (also reading this thread), the following is worth noting:
  • A good student generally refers to one interested in the subject to the point he or she tries to learn more than the minimum needed to get first-rank marks. In contrast, a person suffering from student syndrome receives good marks but only does what is necessary to earn them.
  • The claim there are always three good students may be attributed to the way humans perceive the apparent outliers in data sampled from Gaussian as well as heavy-tailed probability distributions.
  • While it is good for a student to be intelligent, well prepared and receive good marks for their work, this is a completely different concept.
  • Dr White was almost surely trying to tell a joke. Therefore, fact was intentionally mixed with fiction.
In my opinion, learning proper computer literacy skills before entering the university not only prepares a student for modern curricula in all subjects, but further informs that student whether he or she is interested enough in computer science to be a good computer-science student. Back on topic, it seems Fido is still having trouble searching four dimensional spacetime for anything of interest. I suspect depression.

Do you think a well-defined challenge problem would help?
Last edited by ejolson on Thu Oct 31, 2019 6:27 pm, edited 1 time in total.

Heater
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Re: Liberation through Computer Literacy

Thu Oct 31, 2019 4:40 pm

You are right, I don't have the context of that statement by Dr White, so I should not read too much into it.

I suspect academics in many other disciplines at the time may have made similar statements. I don't know about the USA, Canada or elsewhere, but in Britain the 1960's was an era of wanting to educate the populace by building lot's of new universities and pushing them into degree programs.

All well and good but I have always thought that Universities should not be trade schools. Students there should not be there just because it's a perceived road to a good job. If a student does not have the passion for the subject and is only there for the career prospects they are in the wrong place. Wasting their time and everyone else's.

I'm still working on the definition of may latest challenge project idea.
Memory in C++ is a leaky abstraction .

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John_Spikowski
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Re: Liberation through Computer Literacy

Thu Oct 31, 2019 8:13 pm

Heater,

Any chance we can go back to the original challenge and maybe it will evolve into mapping what is visible of our universe?

I have a RPi Tank not a spaceship.
Last edited by John_Spikowski on Thu Oct 31, 2019 8:38 pm, edited 1 time in total.

Heater
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Re: Liberation through Computer Literacy

Thu Oct 31, 2019 8:26 pm

Your wish is my command.

Finding points on a grid it is.

Starting small scale so only stars our galaxy and only those from a certain star catalog.
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John_Spikowski
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Re: Liberation through Computer Literacy

Thu Oct 31, 2019 9:44 pm

The original challenge was to find a few objects in a simple grid. If this challenge is beyond that and the next star wars, I'm out.

Heater
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Re: Liberation through Computer Literacy

Thu Oct 31, 2019 10:38 pm

Yes, the original challenge was to find a few near neighbors to some selected point among a lot of other random points.

I think the data set has to be big enough to make the search computationally intensive, within reason, otherwise it's a trivial challenge. On the other hand it has to be small enough to fit into the typical Pi's RAM space. Say 1GB. I don't want to have to be messing with files on disk to get the job done.

If I remember correctly my original challenge was phrased in terms of a 2048 by 2048 grid of points. I was kind of thinking of an occupancy of 10% or so. So 400,000 points to search.

But of course we don't actually need to maintain a two dimensional array of 4 million elements. Most of which would be empty. We only need to store those random points that are occupied in such a way that they can be searched. We can hold 10 or more million points in RAM I suspect. Not the full 113, 000, 000 points in the chosen star catalog but enough.

I did mention selecting a subset of stars, in some busy part of the sky.
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Paeryn
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Re: Liberation through Computer Literacy

Thu Oct 31, 2019 11:06 pm

I might not be attempting this one Haskell, not after fighting the memory issues last time, though that was more down to the amount of temporary Strings my method created which are far from memory efficient. Strings are stored as linked lists of utf-16 chars, the overheads in 32-bit are huge but in 64-bit are insane!

I'll team up with Kira and do it in C/C++, he may be a good programmer but he's a lousy typist (not to mention how many mice he gets through). I might even try my hand at Rust.
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Heater
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Re: Liberation through Computer Literacy

Thu Oct 31, 2019 11:09 pm

Yeah. As a practical matter it's a pain to have to download and store huge files of test data.

Perhaps it's better for the purposes of the challenge to generate the random "star field" from a know pseudo random number generator algorithm and seed. Small and quick.
Memory in C++ is a leaky abstraction .

Heater
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Re: Liberation through Computer Literacy

Thu Oct 31, 2019 11:14 pm

It's up to you of course but it would be nice to see a variety of languages in the solutions. You are the Haskell guy.

I already started on a Rust solution.
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Heater
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Re: Liberation through Computer Literacy

Thu Oct 31, 2019 11:52 pm

You have not convinced me that getting a fast solution to searching a large number of points is trivial.
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Paeryn
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Re: Liberation through Computer Literacy

Fri Nov 01, 2019 12:26 am

Go on then, I'll do a Haskell version when I have time. Kira says he prefers to do the C version on his own anyway as apparently I disrupt his delicate deep contemplation time (though to me it looks like he's just sleeping on the keyboard).
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ejolson
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Re: Liberation through Computer Literacy

Fri Nov 01, 2019 3:34 am

jcyr wrote:
Thu Oct 31, 2019 11:36 pm
Tatami are rectangular mats, used to completely cover the floor of a room, without overlap.
For reference, this is problem 256 on Project Euler.

https://projecteuler.net/problem=256

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John_Spikowski
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Re: Liberation through Computer Literacy

Fri Nov 01, 2019 5:09 am

ejolson wrote:
Fri Nov 01, 2019 3:34 am
jcyr wrote:
Thu Oct 31, 2019 11:36 pm
Tatami are rectangular mats, used to completely cover the floor of a room, without overlap.
For reference, this is problem 256 on Project Euler.

https://projecteuler.net/problem=256
That seems more reasonable and has a practical use.

ejolson
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Re: Liberation through Computer Literacy

Fri Nov 01, 2019 4:39 pm

John_Spikowski wrote:
Fri Nov 01, 2019 5:09 am
ejolson wrote:
Fri Nov 01, 2019 3:34 am
jcyr wrote:
Thu Oct 31, 2019 11:36 pm
Tatami are rectangular mats, used to completely cover the floor of a room, without overlap.
For reference, this is problem 256 on Project Euler.

https://projecteuler.net/problem=256
That seems more reasonable and has a practical use.
In an attempt to cheer up the lead developer of FidoBasic, I mentioned the Tatami question. Unfortunately, Fido became barking mad and growled, why should I do your homework problems in graph theory?

I tried to explain, it's not about graph theory but carpets. With that the dog developer started whining, carpets bring back bad memories from puppyhood, when I got scolded for digging a hole in one and making another wet.

I could not help remarking how such a scolding was deserved and then went on, Tatami are rectangular mats that--as if by magic--can travel in time. At the mention of time, Fido's ears perked up. What are the technical specifications? My friend K9 is borrowing the Tardis while Dr Who is at the dentist. For me to show up with a substandard tapestry covered with cat hair would be embarrassing. How does a time machine compare with a Tatami?

I assured Fido that Tatami were not covered with cat hair (are they?) and then went on to explain how those rectangular mats are capable of traveling forward in time at the exact rate of one second per second. This seemed to calm the dog developer, who began pawing at the keyboard. For the sake of computer literacy, I hope Fido is not still working on a sluggish bootloader.
Last edited by ejolson on Fri Nov 01, 2019 5:21 pm, edited 5 times in total.

Heater
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Re: Liberation through Computer Literacy

Fri Nov 01, 2019 4:54 pm

John_Spikowski,
That seems more reasonable and has a practical use
Hmm... The likes of Google might disagree. For them the problem of finding a few points from among millions is something they have to do many times every second of every day to earn their daily bread.

On the other hand, I have never seen anyone tiling anything with Tatami.

If I was going to go with non-square tiles in my bathroom they would be Penrose Tiles.
Memory in C++ is a leaky abstraction .

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John_Spikowski
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Re: Liberation through Computer Literacy

Fri Nov 01, 2019 5:16 pm

I was thinking yoga mats might be an application.

My kitty (Savu - Finnish for smoke) thinks it's a good project she can get her claws into.

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