joppy

10 ms·

61.
by joppy 5y ago
Having dead or sick parents and teachers is also a terrible outcome for children.
62.
by joppy 5y ago
The university just needs to set an assignment which needs to be submitted twice: once with citation style A, and again with citation style B. Anyone not using citation management software will quickly start.
63.
by joppy 5y ago
The text dims a bit too fast to read comfortably on my phone (especially since in the latest version of iOS Apple has inexplicably moved the address bar from the top of the screen to the bottom). But this scrolling paradigm is just fantasti
64.
by joppy 5y ago
If my intent is that a certain integer should never be negative, labelling it unsigned does a poor job at conveying this intent because any arithmetic just silently does the wrong thing. 3-4 is some huge number rather than “error”.
65.
by joppy 5y ago
> I adjusted my headlamps down… I was told that the headlight adjustment in some large vehicles are meant to accomodate for weight (2 people in front vs 5 people in vehicle), but it seems that most people simply adjust this as high as it
66.
by joppy 5y ago
I think this is a good policy, and have often been annoyed that I can’t (rules of the university) mark my students down for such absurd answers.
67.
by joppy 5y ago
This is the same as my experience growing up in Australia - right the way from primary school up to university-level subjects, mathematics working is marked and you get almost full points if you solve the problem correctly but just make som
68.
by joppy 5y ago
This isn’t a free marketplace of ideas though - thanks to dubious algorithms and recommendations, not all ideas even have a chance of being seen, let alone the bad ones buried. The echo-chamber phenomenon is like walking into a shop, lookin
69.
by joppy 5y ago
You might have an abstract function f which takes and returns an integer, and you want to figure out if this function has “cycles”, eg if ffffff(n) = fff(n) etc. The numbers used might be enormous, and so trying to store them all is a non-s
70.
by joppy 5y ago
Yeah you're totally right, my bad.
71.
by joppy 5y ago
> If you have a set with two binary operations, then a monoid isn't the correct abstraction. I guess my point is that even if I used "the correct abstraction" here, meaning a ring or something, then the whole newtype setup
72.
by joppy 5y ago
What's wrong with newtypes is that if you want to define "the monoid of integers under addition" and "the monoid of integers under multiplication" (or similar, the second isn't really a monoid because of zero),
73.
by joppy 5y ago
Rotation matrices are still ubiquitous even in systems which use quaternions: if you want to apply a dense linear transformation to a vector (be it a rotation or otherwise), pretty much nothing will beat (in terms of speed) a matrix-vector
74.
by joppy 5y ago
Quaternions are the even part of the Clifford (aka Geometric) algebra associated to a three-dimensional space, so the connection is quite close. This case is also quite special because the quaternions form a division algebra over the real n
75.
by joppy 5y ago
This question seems to always come up on Hacker News - figuring out how to even formulate the statement of theorems in theorem provers such as Lean is a massive research undertaking in itself, requiring much creativity and novel work. Let a
76.
by joppy 5y ago
It’s more like “in a world where every group of n horses are the same colour”, no matter of whether that world is the real world or not, “prove that any group of n+1 horses are the same colour”. This inductive step proves nothing about the
77.
by joppy 5y ago
This is standard induction: let P(n) be some statement about the number n. If you can establish that P(n) implies P(n+1) for all n >= 1, and that P(1) is true, then P must be true for every positive integer. You can find many examples by
78.
by joppy 5y ago
I heard from a friend (have not verified myself) that the paper in which the Magma computer algebra system was introduced is the most-cited paper in the whole of pure mathematics.
79.
by joppy 5y ago
Groups are not inherently discrete - there are many continuous groups (called Lie groups) such as the circle, group of rotations in 3D, etc etc. You can also see this turn up in Fourier theory: the discrete Fourier transform has an underlyi
80.
by joppy 5y ago
What? The mathematics shows correctly on the page for me, and that PDF is missing some chessboard images...
81.
by joppy 5y ago
Trying to stylise the letter M to be distinctive is pretty circuitous - just use an icon of a train! You remove the problem almost entirely, and get a symbol which is easily recognisable even to people who don’t speak the local language. In
82.
by joppy 5y ago
Things fail in the weirdest ways in unsupported environments though, it’s not like the “make transfer” button doesn’t work, it’s more like it might not even show up in the first place. Having 99% of your website work and the last 1% not wor
83.
by joppy 5y ago
Because Svelte can look through the template, and at compile-time determine exactly which parts of the output need to be "surgically updated" in the DOM when some of the inputs change, without needing any runtime like a virtual DO
84.
by joppy 5y ago
I think that software like mathematica is a great tool, and anyone genuinely doing research that would benefit from it should be happy to pay for it as a matter of course. But I can also see many of the downsides to using closed-source soft
85.
by joppy 5y ago
It’s universal portability, but at the cost of only using the lowest-common-denominator features of any random markdown implementation. There are so so many more things that can be done with websites and long-form writing than big standard
86.
by joppy 5y ago
I feel the same way - if computers happened to use base 3 instead of base 2 we could have fixed-width signed integers which are symmetric about zero.
87.
by joppy 5y ago
Trivial, or just straightforward? I don’t think that it’s trivial to know why multiplying by this powers-of-roots-of-unity matrix is interesting, and does the things that it does.
88.
by joppy 5y ago
The post itself shows that it is non-trivial to even boot this hardware with Nix.
89.
by joppy 5y ago
JavaScript is a language where you need to implement your own hash table, since the built-in object only understands key strings, and the built-in Map class only has value semantics when the keys are primitive types (strings, ints, etc), an
90.
by joppy 5y ago
Is microseconds correct? Even with a good connection in online games I’ve only seen ping latencies of 3ms or so, and a more common range on an average connection is 20ms-50ms.

More ›