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amuresan

Moving to exact predicates on top of floating point numbers would be a big speed boost. CGAL does this.
Re:Ask HN: Who is hiring? (December 2024) on Tuesday December 03, 2024 @11:08AM (#42307678)
The link you posted is behind a login, do you have a public profile?
Hi Mihai! This is impressive work!

Are you aware of any other computational maths problems where a sufficiently motivated amateur could make an improvement on the state of the art?

93 is my best score so far
Great game! thanks for sharing
Related to the Coral accelerator, is it usable as a general accelerator outside AI workflows? When I looked into it, there was no general SDK on using the Coral, only an "ingest ML model" compiler.
Not surprising. It always seemed likely to me that there is model bias if you train your models on model generated data, like a feedback loop (second order effects?). Similar to how applying a linear system over and over stretches the inputs in the direction of its largest eigenvector.

Now wait till the generated content is indistinguishable from human content (to humans) and it will be hard to figure out what's in your training set.

Re:Most readable, low eye-strain colorscheme? on Saturday April 08, 2023 @09:32AM (#35492914)
Not a direct answer, but last year I got a 13" eink second screen and it's been the best investment I made for my eye health since getting glasses. The difference was noticeable from the start, at the end of a day without the eink screen my eyes feel tired, similar to sand in your eyes. After a day of using the ink screen my eyes feel a lot better, still relatively tired, but like the tired you get at the end of a day not in front of your computer.

Here's the screen that I got, it's pricey, but in my case was well worth it: https://shop.dasung.com/products/dasung-e-ink-paperlike-hd-f...

Re:The Fourier Transform, explained in one sentence on Sunday January 15, 2023 @08:48AM (#34389341)
What do you mean by crop in frequency domain? Low pass filtering i.e. removing higher frequency components?
Thanks, will give them a try. Any advice on what to get?
Getting an eink secondary monitor for my workstation. I use to get pretty bad eye strain that lasted for days from LCD screens. It got so bad I forgot how it feels to wake up without my eyes hurting. Now it's all gone.

The product offering of eink screens is virtually non-existent, the only usable one for interactive work that I found was the Dasung 13.3", which is the one I got.

Re:Better Geometry Through Graph Theory (2018) on Monday June 29, 2020 @12:53PM (#23679318)
Fair point. At the same time the exact computation paradigm is proof that problems like these can be solved in a rigorous way if you start with the right foundation.

By the way thanks for writing the article, it was a refreshing read.

Re:Better Geometry Through Graph Theory (2018) on Monday June 29, 2020 @08:11AM (#23676817)
One geometric model that actually handles numerical approximations is called exact geometric computation. It's pretty interesting and starts by explicitly tracking arithmetic errors in the operations you do. At its core it's a mix of interval arithmetics and multi-precision floating point. This is something you can do since the floating point implementations on most (all?) CPUs give you strong guarantees on the error bound of floating point arithmetic operations and these are usually within 1 ulp (unit in the last place) of the correct result. Now you have an interval for the result and can build your geometric constructs on interval arithmetic rather than classic, single point scalar arithmetic.

Geometry works with constructs, not numbers. An intersection is a construct, collinearity is a construct, orientation / handedness is a construct, etc. If you define your fundamental constructs to be rigorous then the algorithms you build on top will also be rigorous. If we consider the article's inside-outside test example, this result would be computed based on the intersections (intervals) we've computed. Since we know for sure the correct result is within our interval of error then inside-testing boils down to comparing intervals and we know there are three possible situations here: 1. [a, b] < [c, d]; 2 [a, b] > [c, d]; 3. [a, b] overlaps with [c, d]. In case 1 and 2 we have a robust conclusion and in case 3 we recompute the whole predicate with higher precision until it becomes decidable.

The golden standard for exact geometric computation is CGAL [1]. All the research around it is very interesting and refreshing to read.

[1] cgal.org

Re:Ask HN: What are you building with Rust? for fun or profit on Saturday September 14, 2019 @09:25AM (#20970625)
At https://www.3dhubs.com we're using Rust to build the geometry processing side of our platform, which is the most computationally intensive custom part. Previously it was in C++ and we're a lot happier after migrating to Rust two years ago.
Re:Ask HN: How do you hire top talent in 2019? on Saturday April 13, 2019 @02:28AM (#19651413)
It might also be specific to the niche you're hiring for. What's your field of operation? What technologies / technical disciplines are you looking for?
Re:Ask HN: Show Us Your Personal Website/Blog? on Tuesday February 19, 2019 @07:47AM (#19198536)
https://adimuresan.com/

Personal website that I've been wanting to turn into a blog about computational (differential) geometry, applied mathematics, performance optimization and distributed systems.

Re:Operational Calculus for Differentiable Programming on Monday December 31, 2018 @05:59AM (#18794026)
Could someone with a better understanding of the topic give a brief example of how this can be used in practice?
Re:Ask HN: Books you read in 2018? on Wednesday December 12, 2018 @11:23AM (#18665175)
Will check it out, thanks!
Re:Ask HN: Books you read in 2018? on Wednesday December 12, 2018 @04:26AM (#18662508)
1. La peste (Albert Camus) - entertaining if you're into French existentialism

2. Linked (Barabasi) - insightful and useful to understand that most phenomenon we see in real life follow a power law and what that means

3. Leonardo da Vinci (Walter Isaacson) - surprising how little of da Vinci's real personality is reflected in his modern image

4. Matrix computations – third edition (Gene Golub, Charles van Loan) - good read if you're into linear algebra

5. Giving effective feedback (Harvard business review) - useful for getting an understanding on how to handle human interaction

6. The old man and the sea (Ernest Hemingway) - enjoyed it a lot, a reflection of Hemingway's romantic spirit. Also, a quick read.

7. Screwjack (Hunter S. Thompson) - didn't resonate with me although I am a fan of existentialism

8. Sun and steel (Yukio Mishima) - raw and intimate. before reading this book I'd recommend reading up on Mishima's life

9. Stranger than fiction (Chuck Palahniuck) - somewhat entertaining, more so because it served as a glimpse into Palahniuck's creative process

10. Thinking in Systems: A Primer (Dana Meadows) - useful for understanding that in modern life we have complex systems at work with emergent behavior that we didn't expect. Trying to isolate / model a single component of one of these systems is a flawed approach.

11. Chaos monkeys (Antonio Garcia Martinez) - entertaining, but quite long

12. Weapons of math destruction (Cathy O'Neil) - in a way, similar to Thinking in systems, but at an applied level. Shows how rules in modern society can have unintended negative consequences when hidden negative feedback loops emerge from the complex system they are embedded in.

13. Lolita (Nabokov) - a brilliant novel from many points of view. Although the topic is controversial, it is a book that had to be written.

14. The prince (Machiavelli) - an interesting read. It was intended as a guide to the young price Cesare Borgia from his teacher Machiavelli. The secret to enjoying it is not to judge it by modern morality.

15. Give and take (Adam Grant) - psychology research about giving / taking / matching personality types presented in a book for the masses. I would not read it again; watching a presentation online should be enough to get the point across.

16. Mécanique (Landau, Lifchitz) - refresh of mechanics

17. Do androids dream of electric sheep (Philip K. Dick) - enjoyable and entertaining! I'm surprised how different the feel of the book is compared to the Blade runner films. In the book androids are purely rational beings, whereas the film wraps them in an aura of romanticism.

18. How we learn (Benedict Carey) - decades of learning research condensed in a book

19. Advanced Calculus: A Differential Forms Approach (Harold M. Edwards) - the best math book I've read so far! For me it was eye-opening in a fundamental way. Edwards is truly a gifted teacher.

20. Three men in a boat (Jerome K. Jerome) - enjoyable and amusing

21. Getting to yes (Roger Fisher, William Ury) - negotiation book, nicely written and structured

22. Without a word (Zhang Jie) - historical novel by one of China's most acclaimed modern writers. I don't have a good reference to compare against since this was my first Chinese novel, but overall I did enjoy it. It felt real and raw.

Ask HN: Pros and cons of working as a freelancer?

Let's do some freelancer mithbusting! Which of the following are true in your experience?1. Exposure to a diverse set of work environments;2. Exposure to a diverse set of technologies and domains;3. Finding work when starting out is difficult;4. Finding work becomes progressively easier;5. You don't have time to get bored;6. You have the freedom to work on other projects, including your own;7....

( Read More... | 2 comments | 2 points | on HN )
Pretty cool! How about turning this into a service where other people can lease their own GPU hardware? Either through your website or by offering it as a sort of turnkey solution.
Thank you so much for your insightful and educational response.

Ask HN: Suggestions for low cost homebrew “HPC” beast?

Over the past few years I've been playing around with the idea of building large number crunching applications for fun and personal research. While the applications I had in mind aren't trivially parallel, they should map well to a parallel architecture.There are generally two options for running a big parallel application: 1. going to a commercial provider, which is prohibitively expensive; 2....

( Read More... | 10 comments | 11 points | on HN )
What industries would you say are currently using SLAM?
Re:Lexical Distance Among the Languages of Europe on Tuesday February 02, 2016 @02:25AM (#11018054)
Current theories say it originated from the language spoken between the Black Sea and the Ural mountains [1] and was probably brought to current East Europe during a migration.

https://en.wikipedia.org/wiki/Finno-Ugric_languages#Origins

Re:Pikazo on Friday January 29, 2016 @04:22AM (#10994312)
For people downwoting this comment, please explain why. This is a very pertinent question.

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