stabbles

61 ms·

811.
by stabbles 9y ago
Krylov subspace methods have been the top algorithms for years for solving linear systems Ax = b and eigenvalue problems Ax = λx. They basically find x as a polynomial in A: x = a_0b + a_1Ab + a_2A^2b + ... . Why a polynomial? Because it&#
812.
by stabbles 9y ago
I believe state of the art methods aim for linear time complexity, using the Fast Multipole Method to perform matrix-vector products in O(N) operations rather than O(N^2), and applying that in an iterative solver such as GMRES, which typica
813.
Ask HN: How do you craft your slides?
1 points by stabbles 9y ago|0 comments
814.
Ask HN: What presentation framework do you use for the browser?
1 points by stabbles 9y ago|0 comments
815.
by stabbles 10y ago
Unfortunately people tend to think this game is unfair if you get to choose second all the time.
816.
by stabbles 10y ago
A monoid (weaker than group: doesn't need to have an inverse) is an example of a category, with a single object G (namely the underlying set) and a lot of arrows from G -> G. If you take the natural numbers N = {0, 1, ...} as a set
817.
by stabbles 10y ago
Object-based programming is not about inheritance by definition.
818.
by stabbles 10y ago
I think the most apparent example is that people recognize patterns like `fold` and `map` everywhere once they've seen functional programming. This can be implemented in any language I guess. Most often you'll see explicit & i
819.
by stabbles 10y ago
And some of the familiar linear algebra theorems extend to infinite dimensional spaces. For instance spectral theory of compact operators [1] [1] https://en.wikipedia.org/wiki/Spectral_theory_of_compact_ope...
820.
by stabbles 10y ago
There is a project called ReactPHP [1] which provides a nodejs-like event loop and async execution. However, I think the power of PHP is that it is not designed to be its own server, to run forever in the background and handle all kinds o
821.
by stabbles 10y ago
The suggestion is that any religion or movement having a theme of Light vs Darkness has its roots in Zoroastrianism. I guess it's hard to prove that this is the case. Could be a coincidence as well. Such a theme is quite natural to dev
822.
An Index to Creationist Claims(talkorigins.org)
1 points by stabbles 10y ago|0 comments
823.
by stabbles 10y ago
What I like about Thomas Nagel is that he is one of the few atheists who steps up against darwinism and materialism as an explanation for almost everything. Quoting from The Last Word (1997): "[...] I don't want here to be a God;
824.
by stabbles 10y ago
Mitochondria is the powerhouse of the cell
825.
by stabbles 10y ago
Never heard of petri-nets before, but familiar with ES. Do you have some good references as an intro to petri-nets?
826.
Compile-time primes in modern C++(stoppels.blog)
1 points by stabbles 10y ago|1 comments
827.
Compile-time prime counting in modern C++(stoppels.blog)
5 points by stabbles 10y ago|0 comments
828.
by stabbles 10y ago
I was thinking the same, but don't agree on the latter: using the STL makes code quite compact and easier to follow.
829.
by stabbles 10y ago
Depends on the number of unknowns, sparsity of the matrix, whether you want 3 correct digits or 16, etc. Direct methods as Gaussian elimination with pivoting are proven to be stable. Iterative methods are not but can be a lot cheaper in com
830.
by stabbles 10y ago
Only scrolled through it, but AFAIK if its results are comparable to Kaczmarz, then note that it is extremely slow. If your goal is to solve say a LS problem, why not go for CGLS? http://web.stanford.edu/group/SOL/
831.
by stabbles 10y ago
These problems you sketch can already be overcome by using the approximate eigenspectrum info of the matrix obtained as a by-product of Krylov methods. This has been invented many times, and is used in 'thick restart', 'augme
832.
by stabbles 10y ago
I wrote about this a while ago: https://medium.com/@stabbles/why-you-should-disable-autofill...
833.
by stabbles 10y ago
It also has an include.php file: https://lastpass.com/include.php
834.
by stabbles 10y ago
Maybe you could add this leak to your list as well: https://news.ycombinator.com/item?id=12695451
835.
Show HN: Leaking personal data in your browser(medium.com)
9 points by stabbles 10y ago|1 comments
836.
Why you should disable autofill(medium.com)
9 points by stabbles 11y ago|0 comments