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Ask HN: What problem are you close to solving and how can we help?

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Re: Ask HN: What problem are you close to solving and how can we help?

#461

Post by kjrose »

I've been working on applications of network flow theory and ecological measures to macroeconomics to determine mesoeconomic scale measures for use by decision makers and businesses. These measures use certain properties to determine both stability due to sudden shocks to the economic system as well as what various policy actions will have on the overall health.

This includes entirely different ways of visualizing free trade, etc.

I have made some significant progress in the past year, but I am running into this headache where the papers I need are not easily accessible (or cheap) since I'm not an academic and I'm literally doing this as a for fun side project. I've been trying to find a university or college willing to take me on in some capacity simply to let me get access to academic catalogues, but I am not having that much luck unfortunately.

The best results recently though include some really fascinating stuff that comes from statistical measures that give clarity to how a region would respond to being isolated for any period of time.

Re: Ask HN: What problem are you close to solving and how can we help?

#463

Post by jlokier »

myWindoonn wrote: post #454
jlokier wrote: post #441

Earlier quoted context omitted.

If you're interested in eliminating proof-of-work for ETH, you should really take a look at the proof-of-stake network in progress. Keywords: "Eth2", "proof of stake" and "the merge". When proof-of-stake takes over, there won't be any miners. The block proposal process is done by stakers instead. Some of the incentive issues with miners still exist with stakers, but raw competitive power consumption isn't one of them…

The proposed PoS scheme for ETH will run afoul of regulators as soon as a big-enough crime is financed on ETH. I do not need to put effort into destroying those things; they are ticking time bombs. PoS separates participants into pigs and chickens, and the pigs could find themselves liable as money handlers.

> I do not need to put effort into destroying those things [proof-of-stake blockchains]

You originally said you want to destroy proof-of-work blockchains, and were looking for advice on how to do that with ETH. It's already being destroyed on ETH by proof-of-stake. You asked for advice, that's the advice. You don't need to do anything except wait.

Now you are saying you don't need to put effort into destroying proof-of-stake. Why is that relevant here? It suggests to me your goal is different from what you originally stated. Are you looking to see the destruction of more than just proof-of-work? The destruction of BTC and ETH, even if they switch away to another consensus mechanism?

Re: Ask HN: What problem are you close to solving and how can we help?

#464

Post by bastawhiz »

te wrote: post #416
bastawhiz wrote: post #412

Earlier quoted context omitted.

It's not quite so simple; I need to insert smaller audio files into a larger file at specific time codes.

Splice you parent file at the time stamps, interleave the samples, then concat.

I'm trying to avoid reencoding multiple times, and saving WAV to disk puts serious pressure on storage constraints

Re: Ask HN: What problem are you close to solving and how can we help?

#465

Post by dr_zoidberg »

gurgeous wrote: post #283
udev wrote: post #265

I am blocked on finding a good (defined below) way to determine whether a product description A and product description B refer to the same product. Imagine that a product description is a n-dimensional vector like: ( manufacturerName, modelName, width, height, length, color, ...) Now imagine you have a file with m such vectors (where m is in millions), and that not all fields in the vectors are reliable info (typos,…

I have worked on this problem many times, at many companies. I am working on it again, actually. Usually some combination of scoring and persisting results in CSVs for human review. (edit: I am at a desktop now and I can say a bit more) Here is the process in a nutshell: 1. Create a fast hashing algorithm to find rows that might be dups. It needs to be fast because you have lots of rows. This is where SimHash, MinHas…

With regards to 1, I wonder: why would calculating the Hamming distance be slow? In python you can easily do it like this:

    hamming_dist = bin(a^b).count("1")
It relies on a string operations, but takes ~1 microsecond on an old i5 7200u to compare 32bit numbers. In python 3.10 we'll get int.bit_count() to get the same result without having to do these kind of things (and a ~6x speedup on the operation, but I suspect the XOR and integer handling of python might already be a large part of the running time for this calculation).

If you need to go faster, you can basically pull hamming distance with just two assembly instructions: XOR and POPCNT. I haven't gone so low level for a long time, but you should be able to get into the nanosecond speed range using those.

Re: Ask HN: What problem are you close to solving and how can we help?

#466

Post by minhmeoke »

akkartik wrote: post #421
minhmeoke wrote: post #408

Earlier quoted context omitted.

Your project is quite impressive. And welcome to the world of computer graphics! I'd consider taking inspiration from the following sources: 1. GUI toolkits like QT QML [1] or Android [2]. These typically build a hierarchical tree of different components (eg: start with a root window, which contains panes, which in turn contain text and buttons). Each component may contain different properties (eg: font, color), and…

Thank you for those suggestions! Do you know if any of those tools following either approach has any automated tests? My immediate problem is how to manage the complexity of implementing a layout engine or editor. Somewhere I need something checking that a given asset identifier results in specific pixels. And I'd like the tests for _that_ to be nice to read. It's a bit of a chicken-and-egg problem..

Glad that you found this to be useful!

Android includes the Espresso UI testing framework [1]. Essentially, you can specify matchers that compare your expected values or predicates against an actual object identified by an R.id identifier. It's very powerful (since you can write your own custom matchers) but can be cumbersome to use [2].

[1] https://developer.android.com/training/testing/espresso/basi...

[2] Example Espresso Test: https://github.com/android/testing-samples/blob/main/ui/espr...

https://github.com/android/testing-samples

Alternatively, Squish [3] is a very polished and more elegant commercial testing tool that lets you record test-cases using a GUI tool and convert them into (ideally modularized) methods that verify object properties or compare (masked) screenshots of the GUI:

[3] https://www.froglogic.com/squish/features/

Demo video (starting at 14:24): https://youtu.be/ElH-3MVHPRw?t=864

They abstract away a lot of the functionality using the Gherkin [4] domain-specific language so that tests are easier to read at a high level (but you can still dig down into the underlying programmatic implementation).

[4] https://cucumber.io/docs/guides/overview/

This is probably too much complexity for your use-case, but may provide some ideas or inspiration for what is possible. Perhaps a simplified matcher-style system might be a good starting point though.

Re: Ask HN: What problem are you close to solving and how can we help?

#467

Post by minhmeoke »

bastawhiz wrote: post #464
te wrote: post #416

Earlier quoted context omitted.

Splice you parent file at the time stamps, interleave the samples, then concat.

I'm trying to avoid reencoding multiple times, and saving WAV to disk puts serious pressure on storage constraints

You could use FLAC as an intermediate lossless codec which should reduce storage costs by about 1/2 to 2/3 compared to WAV.

Re: Ask HN: What problem are you close to solving and how can we help?

#468

Post by dtjohnnymonkey »

jordwest wrote: post #88

I want to bring back old school distributed forum communities but modernise them in a way that respects attention and isn’t a notification factory. Mastodon is a pretty inspirational project but the Twitter influence shows, I miss the long form writing that was encouraged before our attention spans were eroded. Not at all close to solving it, but it’s been on my mind for a long time. Would love to hear if there are o…

Reddit is building something like this https://www.reddit.com/community-points/

Re: Ask HN: What problem are you close to solving and how can we help?

#469

Post by sabageti »

graphcolorer wrote: post #312
sabageti wrote: post #228

Earlier quoted context omitted.

What are the needs in time?

Can take as long as needed as it only needs to be colored one time. About 10,000 nodes, reasonably dense (about half the nodes will have 1,000+ edges).

What did you try to color the graph ? CSP ? Classic backtracking ? With how many colors it must be colored ?

Re: Ask HN: What problem are you close to solving and how can we help?

#470

Post by ID1452319 »

There is a juxtaposition in the UK job market. We have millions of people working in low-paid precarious jobs in retail, food service, warehousing etc. while simultaneously companies complain that they cannot recruit into highly-paid, skilled roles due to a lack of candidates.

Given that you can study Introduction to Computer Science from Harvard University, online, for free and in your own time, it seems like the barriers to building skills is lower than ever.

However, many people are put off or intimidated by the idea of studying such a course. My solution to this is some kind of mentoring, either 1-to-1 or more likely in small groups. However, this is very resource intensive for my idea to scale. I'd be very interested to hear how others might approach this, both the mentoring or the underlying encouragement to study.

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