DE wrote:
* prefer operator () to operator[]. operator[] is never needed and is less generic
internally i alwayse use () but [] are provided for users' convenience
It's really not needed. operator(i) is the same semantically and I don't think any STD concept require []. Having matrix be real function object is also a good way to use htem more generically.
but they are handled differently (different public interface) vector is modeled after std::valarray (everybody knows about valarray) and matrix is just a generalization of std::valarray behavior oh and vector is a column-vector
Just don't name it vector then. In lin. Alg. a vector is a matrix with one dimension equal to 1. if not, ppl will wonder why matrix*vector doesn't mean what they think it does.
what do you mean by policy?
You should have one matrix class whose tempalte parameters allow for customization. Want a matrix with static data : matrix<float, settings<static_> >
don't get it (forgive my unliteratedness)
NRC allocation states that a array of N dimension is stored as N array of pointers, each pointinng to sub-element of the next one, the last one being a large, monolithic contiguous array of data. This allow for N-dimensionnal acces via chains of [] and ensures cache locality at the latest level. It's easy to write, can be recursively extended for arbitrary dimension number and ease the writings of code that requires you to extract or work on complex sub-array. performances of access is roughly the same that T* (within a 2% margin). this requires to have an iterface that takes smthg lika boost::array for handling set of dimensions and indexing. sample 2D code here : http://codepad.org/nDy8z2iG of course this has to be hidden in the implementation.
i've heard and forgotten i've seen and memorized i've done and understood ...or something like thi which means ?
-- ___________________________________________ Joel Falcou - Assistant Professor PARALL Team - LRI - Universite Paris Sud XI Tel : (+33)1 69 15 66 35