Re: [Boost-bugs] [Boost C++ Libraries] #4034: better vector/matrix assignment (or initialization)

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #4034: better vector/matrix assignment (or initialization)
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2010-03-28 20:39:42

#4034: better vector/matrix assignment (or initialization)
------------------------------+---------------------------------------------
 Reporter:  guwi17            |       Owner:  guwi17      
     Type:  Patches           |      Status:  new         
Milestone:  To Be Determined  |   Component:  uBLAS       
  Version:  Boost 1.42.0      |    Severity:  Optimization
 Keywords:  assigment         |  
------------------------------+---------------------------------------------

Comment(by nasos_i@…):

 I attach a whole new version of the assignment operator
 (assignment.patch.tar.gz). The patch contains a header assignment.hpp and
 unit tests (test_assignment.cpp). I think some sophisticated assignment
 tricks can be used with those operators (still finding news ways they can
 be used). This version is a complete rewrite, but in terms of interface
 the differences are the following:

 0. Name was changed to assignment after Boost.Assignment.

 1. non_vector(T i) was removed and was replaced by move(T i)

 2. move(T i, T j) was added for matrix expression traversing

 3. Absolute traverser was added so that move_to(T i) and move_to(T i, T j)
 can be used on vector and matrix containers respectively.

 4. mat1 << mat2, ... support was added

 5. A simple traits mechanism so that fill policy can be chosen was
 implemented. This allows for:

 {{{
 compressed_matrix<double> cm;
 cm << fill_policy::sparse_push_back(),
       1, 2, mat, vec, vec_expres, ...;
 }}}

 6. A number of test cases were added in the spirit of
 http://svn.boost.org/svn/boost/trunk/libs/numeric/ublas/test/test_coordinate_matrix_sort.cpp.


 They patch looks ready for merging to ublas, but of course this is only
 under my eyes. Comments, suggestions are HIGHLY desired.

 Beside the sparse_push_back policy, performance was not considered but
 with the fill_policy tag it looks that we can implement more sophisticated
 assignments now.

 I can write a small tutorial or guide, but I would like to now the format
 I should provide it in.

 Best
 Nasos

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/4034#comment:1>
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