Hacker News Reader

It's where people get together to have a discussion around a set piece of reading. In this case the reading is of a textbook, and the discussion is intended to help everyone understand the material.

RiderOfGiraffeson Tell HN: I am doing online reading sessions on analytic number theory

Following a couple of links gives this:

https://twitter.com/susam

RiderOfGiraffeson You can now download the source code for all Infocom text adventure classics

Discussion: https://news.ycombinator.com/item?id=19672436

RiderOfGiraffeson Ask HN: How do you handle code ownership?

That's what dictionary.com says, and that's true in some places, but in other places "guys" is definitely gendered.

Imagine a group of cishet men saying : "I'm off to the strip club to see a bunch of guys taking their clothes off and dancing in a provocative manner."

Does that seem reasonable? If not, then the term "guys" is gendered.

On top of that, most of the women I know feel that "guys" is a term that excludes them. That's enough for me to avoid using it.

RiderOfGiraffeson Ask HN: How did you get introduced to HN?

In searching about an obscure fact concerning languages I found Paul Graham's essay "Beating the Averages"[0] I found it interesting, and started to read some of the other essays. As a quick hack I then drew a diagram of the obvious connections between them[1]. Similarly, I then used a PageRank-style ranking of the essays[2].

I sent the results to Paul Graham, who said I should submit them to HN, of which I'd never heard. I did so, and they pretty much sunk without trace, as do so many of my submissions. Even so, I read some more, and stayed for a while.

[0] http://www.paulgraham.com/avg.html

[1] https://www.solipsys.co.uk/new/PaulGrahamEssays.html?HNrj06

[2] https://www.solipsys.co.uk/new/PaulGrahamEssaysRanking.html?...

RiderOfGiraffeson Ask HN: How did you pick your HN handle?

Well, I have a giraffe, and I ride it. I've also ridden other giraffes.

So, well, RiderOfGiraffes.

RiderOfGiraffeson A prime number whose binary representation looks like a giraffe

I guess I should comment here, but I don't have much to add. Most of the questions that arise naturally about how this was done, and about primes in general, have already been asked and answered.

Still, given my username I should add something ...

So if the size was prime x prime then the fact that the number of bits is a semi-prime tells you the size of the image, even if all you have is a stream of digits. Then the "noise" at the end will tell you what the least significant bits are, and hence you get an image without very much ambiguity.

Just thought I'd mention that.

RiderOfGiraffeson Ask HN: Confused by a friend in discussion of variables

What you have there is an l-value, which is an expression that evaluates to a location into which a value can be placed.

A variable is a single name and is the simplest example of an expression that is an l-value.

RiderOfGiraffeson “As We May Think” – Vannevar Bush and the Memex

If you want to see previous discussions of this material, a good link is this one:

https://hn.algolia.com/?query=Vannevar%20Bush&sort=byDate&da...

RiderOfGiraffeson God's Number is 20 (2010)

I always hesitate - some people hate it, others appreciate it. I think it's worth cross-connecting previous conversations, because I see the HN discussions as a resource. Others seem to think it should all be ephemeral and throw-away.

Having said all that, I hope this gets some new discussion.

RiderOfGiraffeson God's Number is 20 (2010)

Previous discussions are closed now, of course, but in case anyone is interested in the HN thoughts and opinions, here are some links.

The result was announced some 6 years ago, and there was a long discussion about it here: https://news.ycombinator.com/item?id=1587340

It was submitted again three years ago with another lengthy discussion: https://news.ycombinator.com/item?id=7374994

The other submissions had no discussion:

https://news.ycombinator.com/item?id=3921215 (1689 days ago)

https://news.ycombinator.com/item?id=1606717 (2315 days ago)

RiderOfGiraffeson How many samples do you need to take to know how big a set is?

Techniques like this were used in WWII to estimate the number of tanks the Germans had, given only limited information about the serial numbers of some.

https://en.wikipedia.org/wiki/German_tank_problem

RiderOfGiraffeson Get ready for Bluetooth mesh

With the recent problems of DDoS's from simplistic devices on the Internet of Things, this worries me. Who will ensure that the devices are paired only with things they are supposed to be paired with? Who will prevent a rogue agent from connecting to your mesh and overwhelming it?

I come from an age when everything was cool, fun, exciting, and everyone played nice. Email didn't have to be secured, messages could be sent directly to terminals, and commands could be executed without worrying that people would strip your machine, take your details, empty your bank account, and turn it into a spam relay.

Where are the security details?

RiderOfGiraffeson Software Checklists – can they be useful?

Betteridge's Law of Headlines[0] says the answer is "No."

[0] https://en.wikipedia.org/wiki/Betteridge%27s_law_of_headline...

RiderOfGiraffeson More effective random algorithm; q=n^(1−δ) vs. q=n^(1/2−δ)

This would appear to be an update of the paper that lots of people have written about. The main discussion is here:

https://news.ycombinator.com/item?id=11719543 (157 comments)

Other submissions, some with a comment or two, here:

https://news.ycombinator.com/item?id=11754074

https://news.ycombinator.com/item?id=11725991

https://news.ycombinator.com/item?id=11723319

https://news.ycombinator.com/item?id=11715677

https://news.ycombinator.com/item?id=11713454

https://news.ycombinator.com/item?id=11712636

https://news.ycombinator.com/item?id=11709112

RiderOfGiraffeson Ask HN: Which college or university did you attend?

Bachelors degree at Monash University, Melbourne, Australia.

Masters (equivalent) and PhD at Cambridge University, UK.

RiderOfGiraffeson Ask HN: How did you come to know about HN?

I was looking to write a spam filter and came across Paul Graham's essays. I read them all, then produced a graphic of relationships between them:

http://www.solipsys.co.uk/new/PaulGrahamEssays.html

I haven't updated that in ages - not sure I still have the code for it.

I send a link to that to PG, and he said I should submit it to HN.

So I did.

Original: https://news.ycombinator.com/item?id=368657

Revisited: https://news.ycombinator.com/item?id=397408

Wow. 2008/11/18. Over 7 years ago.

RiderOfGiraffeson What to say when they ask you: how much do you make

So here's something that bothers me about this kind of blog ...

I've found several typos and other grammatical issues, and I'd love to be able to provide quick fixes for them. It's of no real value to me, but I've got something from the article, and I'd be happy to give back a small amount of time to help make it a little better.

But I have to register, check my email, use the password sent to me in plain-text, login, re-load, find the comment box, and then start typing. It's almost like they don't want comments.

But without hurdles like this a blog is quickly over-whelmed with spam, and other even less savoury material. I have an idea as to how to solve this, but I don't have the time to acquire the necessary skills to implement it, and don't really care enough to bother. And so the world remains more broken than it need be.

Which I find disappointing.

RiderOfGiraffeson Job Skills Companies Want but Can’t Get

Yes, all beautifully presented, very whizzy, graphics flying all over. For me? Completely unusable. Nothing stays still long enough for me to work out what anything means. A total triumph of presentation over usability.

One word: Tufte.

RiderOfGiraffeson Ask HN: What would you call this?

A "CoLocation" or "CoLoc" for short.

Coin a short, memorable term, then use both terms everywhere until your users have been around for a time. As a user gets more experienced on the site, drop the longer term and use the "jargon" term. It's a novel concept, it deserves a neologism.

RiderOfGiraffeson Steve Ballmer Steps Down From Microsoft’s Board

https://news.ycombinator.com/item?id=8198886

RiderOfGiraffeson The most common errors in undergraduate mathematics

It goes deeper than that.

Many things in mathematics are defined in a manner that is consistent and convenient. Defining 0! to be 1 is a similar case. In doing so nothing goes wrong, and the binomial theorem becomes simple and convenient to state. Without defining 0! as 1, it's a dreadful mish-mash of special cases.

Similarly with 0^0. Considering x^y where x and y are complex numbers, there is no consistent single value as x and y each approach 0. So in the reals and the complex numbers we leave 0^0 as undefined. However, in the case of natural numbers there is a case for declaring 0^0 to be 1. That's to make it convenient to talk about the set A^B as the collection of functions from B to A. When we do that we get |A^B| = |A|^|B|.

There is more than expected in mathematics that's defined for convenience.

RiderOfGiraffeson How to Land a Job as a Computer Security Analyst

You're keen on this story - you've submitted it twice before:

https://news.ycombinator.com/item?id=8179473 3 points, 12 hours ago

https://news.ycombinator.com/item?id=8176770 3 points, 22 hours ago

RiderOfGiraffeson Print this file, your printer will jam (2008)

    > The Black Team link inside
    > your link is broken ...

Fixed - thank you.

RiderOfGiraffeson The Parable of Indentation

It looks to me like it has a bug - it doesn't seem correctly to factorize anything with a square factor. It also only need to loop up to sqrt(x), not x, but that's an efficiency issue. It also doesn't correctly use an early abort when x has had factors divided out.

There are more problems. Personally, I'd worry more about them than the indentation, but if code layout is your biggest problem, go for it.

RiderOfGiraffeson [dead]

Flag it and move on ...

RiderOfGiraffeson Source code stolen from GitHub.com

You do realise this is satire, right?

RiderOfGiraffeson Ask HN: Trying to pin down both algorithm and problem it solves ...

Nice guess, but no - I know the Bloom filter, what it does, its limitations, its strengths, how it works, and how to implement it. It's one of the tools I have to hand already.

But I can see how that nearly matches by description, so it would be a good match. Thanks.

RiderOfGiraffeson The UK "Porn" Filter Blocks Kids' Access To Tech, Civil Liberties Websites

  > As of now I'm thinking that I'll never block my kid from
  > looking at any kind of content. If she happens to come across
  > some nudity or sex and she has questions about it I'll be open
  > and honest and explain it.

There's some really, really nasty stuff out there. Really nasty stuff. Not just people having sex, but some brutal stuff that a medic friend of mine says gave him significant nightmares for some days.

It's not just about nudity and sex. If it were I'd be less ambivalent. As it is I feel that you're being a bit naive.