cschwan
cschwan on Hacker News
Compile time is the most efficient way (IMO) to deal with all the types that can appear (also in intermediate steps of a calculation). I found this idea first realized in this implementation:
https://github.com/JaapSuter/Vital. According to the comments in the code is from 2004 so it did could not make use of C++0x, which is why I adopted it rewrote it for C++11. This was motivated by an actual problem I had to solve but, sadly, it turned out GA isn't fit for it.
German here. I got addicted to it when, as a teenager, I saw them in our local library. The 3D covers of the "silver books" really got my attention! Inside they had, in addition to the story, extremely detailed cross sections of the space ships that occurred in the series. The dimensions and ideas the authors are really (in a positive way) crazy/gigantic. I also liked that the series was more or less one connected story. The authors regularly keep unsolved puzzles, just to explain them years later!
One day I found out that the newsstand on our train station sold current copies of the series and I was amazed by the fact that they already sold more than 2000 issues (Current edition is at ~ 2800)! The silver books I read before were actually just a streamlined version of ten or so issues. So I starting reading the "first edition", and also bought reprints ... in the end I think I read maybe half the the whole series, but two or so years ago I finally hadn't the time keep up.
This is a really great book! It covers a lot of physics and gives plenty of insight on the relation of geometry and physics. It even made me program this library:
https://github.com/cschwan/hep-ga (shameless self-advertisement).
Did anyone find the authors commits in glibc's repository? Would be nice to know what he really changed and when.
How would concepts simplify this?
"Relaxed requirements for constexpr" is an item that I wish would have gone into C++11. Once have you multiple code paths and need to loop over variables constexpr functions get really unreadable.
One thing the C++ standard library IMO needs is a range library, e.g. something like Boost Range. I often would like to use the "range-for" but when I am not looping over all the elements of a container its useless in that case.
The techniques he used are very similar to "Expression templates". If you are a C++ programmer and haven't heard of it, look it up. There are not many libraries actually making use of it, but Boost uBLAS is an example. I think expression templates give you a good idea what one can achieve with C++ (whether this is a good idea is another question).
OT: That's also why I love the language - there are plenty of ways to solve a problem and C++, unlike other languages, does not force me to solve a problem "the right way".