3
0
mirror of https://github.com/triqs/dft_tools synced 2024-11-01 03:33:50 +01:00
Commit Graph

8 Commits

Author SHA1 Message Date
Olivier Parcollet
b534936589 Fix matrix * alias issue and adapt det_manip
- The previous version of the * operator for matrix was too clever.
It was giving a lazy object and then rewriting C = A *B into gemm (a,A,B,0,C).
The pb was in case of aliasing : when e.g. C = A, or is a part of A.
gemm is not correct that case, and as a result generic code like
a = a *b
may not be correct in matrix case, which is unacceptable.

- So we revert to a simple * operator for matrix
that does immediate computation.
Same thing for matrix* vector

- we also suppress a_x_ty class.

-> for M = a * b,
when M is a matrix, there is no overhead due to move assignment
-> however, when M is a view, there is an additionnal copy.

-Correctness comes first, hence the fix.
However, if one wants more speed and one can guarantee that
there is no aliasing possible, then one has to write a direct gemm call.

-> det_manip class was adapted, since in that case, we can show there
no alias, and we want the speed gain, so the * ops where replaced
by direct blas call (using the array blas interface).

-> also gemm, gemv, ger were overloaded in the case the return
matrix/vector (i.e. last parameter of the function) is not an lvalue,
but a temporary view created on the fly.
2013-09-11 18:49:22 +02:00
Olivier Parcollet
2c542647fd clef : new version using lvalues and moving rvalues
- change : all objects are by default
  stored now by reference, not by copy any more.
  Unless the trait force_copy_in_expr is true.
- rvalue refs are moved into the tree
- simplifies a lot the writing of lazy method, objects.
- added a macro for methods
- tests ok. Further check needed to control absence of copies...
- improved documentation
2013-09-08 15:04:12 +02:00
Olivier Parcollet
c8fcb40164 arrays : rm linalg/determinant and inverse (links)
It is clearer to have only one file :
det_and_inverse.hpp
changed the included in tests.
2013-08-27 13:43:57 +02:00
Olivier Parcollet
6fa737978e arrays: remove .len (redundant)
.len -> .shape
with same syntax.
Made a few necessary corrections here and there.
2013-08-27 13:43:57 +02:00
Olivier Parcollet
bd4926157c [API BREAK] rename directory gf -> gfs 2013-07-29 11:53:02 +02:00
Olivier Parcollet
40f8cb5c18 [API BREAK] gf : rename namespace gf->gfs
- necessary otherwise the class gf and the namespace have
the same name, leading to some confusion, and need to qualify
some functions (specially on gcc).
Same naming conventions as arrays.
2013-07-28 21:11:28 +02:00
Olivier Parcollet
fc2a620eae arrays: new ref counting and weak views
- improve the mem_block and shared_block.
- the reference counting is now done in the mem_block and shared_block, removing the need of shared_ptr.

- speed tests shows that shared_ptr is very slow (due to thread safety?)
the new version is much better, though not perfect.

- Hence introducing weak views.

- also :
-- clean the guard mechanism for python (to allow returning from python without any python ref left).
-- clean code, add documentation for mem_block
-- remove nan init, which was not working, and corresponding test
-- serialisation of view still unchanged (need to forbid serialization of view ??).

- tests ok, incl. valgrind tests.
2013-07-23 08:13:44 +02:00
Olivier Parcollet
f2c7d449cc First commit : triqs libs version 1.0 alpha1
for earlier commits, see TRIQS0.x repository.
2013-07-17 19:24:07 +02:00