Re: log(n) amortized growth for containers
On Friday, 11 December 2015 at 03:55:27 UTC, Andrei Alexandrescu wrote: Does anyone know of a plotter that supports logarithmic integral? Of course better ideas about all of the above are welcome! Yes, my go-to for my university plotting needs is SageMath. Here is the plot of the two functions, the red one is without the li(x). The vertical axis scale is logarithmic. https://sagecell.sagemath.org/?z=eJyVjk0KgzAQhfeCdxjcmNAI1mXBK_QIlWAmaWhMZEzB9vRNBDdFCt3NPL73o1CDZiu_QFkAEMYneVgFdLcrc8EM1kc0JF1CODQHcnPmvCzKQqUgk4O-c9bNtoGZm6GHZZQxIg2zC5FNcmZaAElvkHXi3LacC9ByxDG4QH3lrLlHQ4i-EoDK7PouTZIeSIt9Y9-1-9vXSy1ykcN04mTT6lfNc__pYID5NYBQ_V_zAe2Da2c=&lang=sage
Re: log(n) amortized growth for containers
On Friday, 11 December 2015 at 03:55:27 UTC, Andrei Alexandrescu wrote: To figure a growth schedule that leads to log(n) work per element, a differential equation must be solved: s(n) / s'(n) = log(x) where s(n) will be the (continuous extension of the) growth schedule's sum, i.e. s(n) = f(1) + f(2) + ... + f(n). In other word, s(n) is how many elements we moved around, and s'(n) is the capacity after n steps. The division gives us how much work was done per element. To verify, if s(n) = n, you get O(n) work per element, i.e. quadratic behavior for linear capacity growth. If s(n) = 2^n, you get O(1) work per element. So I entered the equation above in Wolfram: https://www.wolframalpha.com/input/?i=y%28x%29+%2F+y%27%28x%29+%3D+log%28x%29 I like this approach to amortized analysis. I have a question, though, the diff eq you have is s(n) / s'(n) = log(x) But the WolframAlpha query solves for effectively: s(n) / s'(n) = log(n) Why does x = n? Shouldn't x be s'(n), so that s(n)/s'(n), how much work was done per element, is bounded by the number of elements appended (that is about the capacity s'(n))? I thought number of elements != n, but rather something between s'(n) and s'(n-1)?
Re: Need DUB pull request reviewers
On Tuesday, 15 December 2015 at 08:12:59 UTC, Sönke Ludwig wrote: We have a current shortage of reviewers for the DUB repository [1]. Martin is more or less the only one apart from me, but we are both currently too busy to get this done in a timely manner. If anyone can spare a few minutes (maybe even regularly), that could be a great help, even without specific knowledge of the code base. Thanks, Sönke [1]: https://github.com/D-Programming-Language/dub/pulls?q=is%3Aopen+is%3Apr Sure, I'd love to help out. I am extraordinarily idle for the next month, at least.
Re: Trying to build dlang.org - what am I doing wrong
On Thursday, 17 December 2015 at 08:48:21 UTC, wobbles wrote: So - the conversation about the website/documentation piqued my interest a bit and I decided to have a go at making the documentation more readable. However, reading the instructions from: http://wiki.dlang.org/Starting_as_a_Contributor#Fetch_and_build_dlang.org It should be a simple matter of: ```bash mkdir -p ~/code; cd ~/code git clone https://github.com/D-Programming-Language/dlang.org cd dlang.org make -f posix.mak LATEST=2069.2 ``` However, I get a std.net.curl error during compilation of dub (luckily dlang.org doesn't depend on dub, so it doesn't particularly matter and I can carry on with my tinkering). http://pastebin.com/q41AnJyr I assume theres a problem with the makefiles here - or is it stupid user syndrome? Do you have libcurl installed? I think it's required to build dub.
Re: Unions and CTFE
On Friday, 18 December 2015 at 14:30:25 UTC, Gianni Pisetta wrote: Hi all, i'm coding a parametrized crc implementation that can support most of the standards. I want to make it work with CTFE and i stumbled upon a difficulty when using std.bitmanip.nativeToLittleEndian and std.bitmanip.nativeToBigEndian. The code below is the concept used by EndianSwapper and it does not compile because of unions and CTFE. Also as the error message is very obscure, is it intended behaviour or a bug? I think it's intended behavior. According to http://dlang.org/changelog/2.065.0.html#ctfe-overlapped-field "Bit image reinterpretation by using two overlapped union fields is not allowed during CTFE."
Re: Redesign of dlang.org
On Saturday, 19 December 2015 at 14:33:35 UTC, Jacob Carlborg wrote: [3] http://www.googledrive.com/host/0B7UtafxGD9vESlB3aFBxcjNPOXM This looks incredible. I think the layout is a huge improvement from the existing one. I do wish there were a one-click link to the forums on the navigation-bar, instead of a Community dropdown. I personally do not like dropdown menus in navigation bars like that. I'd rather only the most important pages be available there as direct links.
Re: Redesign of dlang.org
On Sunday, 20 December 2015 at 02:04:30 UTC, Jakob Jenkov wrote: If the D website maintainers are to put an effort into changing its design, would it not be preferable to go "all-in" and jazz it up, e.g. like http://www.scala-lang.org/ ? I would like to know this, too. Scala's website is really beautiful. But, I would prefer a design like https://ocaml.org/ -- simple, clean, and efficient.
