joppy

16 ms·

121.
by joppy 5y ago
There’s a difference between socialising where you can say something dumb, and your friends will say “that was dumb haha” and everyone will move on with their lives, and socialising where you can say something dumb, someone posts it on soci
122.
by joppy 5y ago
I would say that your stipulation is (if anything) the wrong way around - most people I know would limit representation theory to linear actions on a vector space (or module over a PID), but would not limit it to a group G: there are grou
123.
by joppy 5y ago
Yeah I was going to say, this sounds like a normal way of getting around the literature. We were taught to start mostly with review/summary papers from high-quality places, and work our way out from there.
124.
by joppy 5y ago
The set of positive integers starts {1, 2, 3, …} and there are no positive integers smaller than 1. On the other hand the set of positive real numbers has no smallest element, since for any positive real number x, the number x/2 is sma
125.
by joppy 5y ago
In a field like crypto you also have the concern that someone might copy your implementation and actually use it - this is fine if your specialty is crypto implementation (resistant to side-channel attacks and so on), but if your specialty
126.
by joppy 5y ago
It’s obscure unless you’re a classical musician (or a pitch/tuning nerd): a lot more people than just piano players know of Bach’s work.
127.
by joppy 5y ago
I guess this must be true, but from the sidelines it seems that “the set of points 1 metre from this particular point” and “the solution to this particular second-order differential equation” are quite different things. Any competent studen
128.
by joppy 5y ago
In Riemannian geometry (i.e. GR) each point has some local invariants associated to it, a famous one being curvature. "Local" here means that it only depends on the metric in an arbitrarily small disc/ball around the point. S
129.
by joppy 5y ago
“Having access to such a room is your own responsibility”… It might be a little much to ask for during a pandemic where people are stuck in places they didn’t expect to be for a long while though, with a whole bunch of other people also stu
130.
by joppy 5y ago
This is such a fantastic article. When I was doing my undergraduate thesis on lock-free and wait-free data structures, it was so difficult to find resources that explained these things in a straightforward way (or indeed in any way at all).
131.
by joppy 5y ago
“ If you code to just the DOM - that is is where you will stay. Forever.” Svelte native exists… The VDOM which mirrors the document DOM is an implementation detail of React, as something sitting between the actual DOM, and the VDOM fragment
132.
by joppy 5y ago
Lots of vdom frameworks are more than fast enough to run business-style SPA applications, but start being very laggy for data visualisation kind of work, or anything where complicated animation combined with user interaction is involved. Th
133.
by joppy 5y ago
I've not used Vue, but how does this solve the problem? In most of my own sites, whatever preprocessor (eg markdown -> html) I use is instructed to replace mathematics with something like <span class="math">z = \frac
134.
by joppy 5y ago
The "server-side rendering" aspect of KaTeX is (and always has been, as far as I'm aware) front-and-centre on their landing page [1]. It allows you to input LaTeX and output HTML ready for inclusion server-side - the only thi
135.
by joppy 5y ago
Yes, it makes total sense for the garbage collector to be tightly coupled to the memory allocation system, which is also tightly coupled to code generation (as is done in the case of various high-performance managed languages: Java, C#, Has
136.
by joppy 5y ago
“Arguably, the main reason why costs have gone up in [healthcare and education] is because society is richer, and thus more willing to bear the cost of better facilities and higher wages for healthcare and education workers.” Please show me
137.
by joppy 5y ago
Isn’t this an argument for better code review, rather than against comments?
138.
by joppy 5y ago
Differentiation is a function that takes a function and spits out a different one. (This may fail at points, but wherever the function is smooth enough, you get a corresponding point on the derivative). It is relatively simple to define, if
139.
by joppy 5y ago
There are two ways you can define the hotel as being full: 1) The hotel is “full” if all the rooms are occupied. 2) The hotel is “full” if there is no way to rearrange the existing guests to leave an empty room. These two definitions of “fu
140.
by joppy 5y ago
Is it normal to deal with returns over time as log-returns log(R) rather than simple returns (R - 1) for this reason? The average log return does the right thing.
141.
by joppy 5y ago
I think this really hits at why the identity is so famous: people tend to have been introduced to pieces in entirely separate ways, and from that perspective it’s quite surprising to see them all come together to create something nice.
142.
by joppy 5y ago
I agree with you on the incomprehensibility of mathematics Wikipedia pages, even as a working mathematician I can really only read the pages about content I already know in-depth. But Wikipedia (and many other reference-type sources) are no
143.
by joppy 5y ago
The alternative being the pretty-much-just-as-short indices.map(i => myObjectArr[i])?
144.
by joppy 5y ago
Log probabilities are used a bit for this, and most numeric packages (numpy for instance) have special functions for computing log(1+x) which are more accurate when x is tiny.
145.
by joppy 5y ago
That really depends on how you define Spin(3), for example some would define it as the compact simply-connected Lie group of a certain type, at which point the unit quaternions model of Spin(3) is as good as any other.
146.
by joppy 5y ago
That does sound super weird but I can see how it would work! I’d probably still prefer a stylus though :P
147.
by joppy 5y ago
This is right - asymmetric crypto is awesome but just not anywhere near as fast as something like AES for chewing through chunks of data. So some anonymous asymmetric crypto (Diffie-Hellman or similar) is used to set up an encrypted channel
148.
by joppy 5y ago
During my time I spent in the USA (I’m from Australia), I was very surprised at the way money and transactions worked. This was 2014/2015 - in Aus pretty much every consumer bank already had paywave (or whatever compatible technology)
149.
by joppy 5y ago
Agreed - what a great story!
150.
by joppy 5y ago
Yeah, tablet and stylus is one of the best solutions for this. Even finger-on-iPhone is pretty janky-looking.

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