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Added SM Splitting with doc version in Fortran skelleton plus Fortran/C interface.
This commit is contained in:
Francois Coppens
parent
181f662c68
commit
1ee9635590
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@ -88,6 +88,17 @@ from applying the updates to the original matrix.
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| ~Slater_inv~ | ~double[Dim*LDS]~ | inout | Array containing the inverse of a Slater-matrix |
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| ~determinant~ | ~double~ | inout | Determinant of the Slater-matrix |
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*** Requirements
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* ~context~ is not ~QMCKL_NULL_CONTEXT~
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* ~LDS >= 2~
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* ~Dim >= 2~
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* ~N_updates >= 1~
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* ~Updates~ is allocated with $N_updates \times Dim$ elements
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* ~Updates_index~ is allocated with $N_updates$ elements
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* ~breakdown~ is a small number such that $0 < breakdown << 1$
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* ~Slater_inv~ is allocated with $Dim \times Dim$ elements
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* ~determinant > 0~
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*** Pedagogical kernel source (in Fortran)
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The following source code written in Fortran is inteded to illustrate how the kernel works. Even though the kernel is
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able to do numerically correct computations, it does not do it in the most efficient way possible. It should therefore
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@ -256,18 +267,6 @@ integer(c_int32_t) function qmckl_sherman_morrison_naive_doc &
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end function qmckl_sherman_morrison_naive_doc
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#+end_src
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*** Requirements
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* ~context~ is not ~QMCKL_NULL_CONTEXT~
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* ~LDS >= 2~
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* ~Dim >= 2~
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* ~N_updates >= 1~
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* ~Updates~ is allocated with $N_updates \times Dim$ elements
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* ~Updates_index~ is allocated with $N_updates$ elements
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* ~breakdown~ is a small number such that $0 < breakdown << 1$
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* ~Slater_inv~ is allocated with $Dim \times Dim$ elements
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* ~determinant > 0~
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*** C headers (exposed in qmckl.h)
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#+CALL: generate_c_header(table=qmckl_sherman_morrison_naive_args,rettyp=get_value("CRetType"),fname=get_value("Name"))
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@ -565,24 +564,23 @@ qmckl_exit_code qmckl_sherman_morrison_naive(const qmckl_context context,
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return qmckl_sherman_morrison_naive_hpc(context,
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LDS,
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Dim,
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N_updates,
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Updates,
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Updates_index,
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breakdown,
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Slater_inv,
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determinant);
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N_updates,
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Updates,
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Updates_index,
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breakdown,
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Slater_inv,
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determinant);
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}
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#else
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return qmckl_sherman_morrison_naive_doc(context,
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LDS,
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Dim,
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N_updates,
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Updates,
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Updates_index,
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breakdown,
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Slater_inv,
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determinant);
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LDS,
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Dim,
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N_updates,
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Updates,
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Updates_index,
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breakdown,
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Slater_inv,
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determinant);
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#endif
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return QMCKL_FAILURE;
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@ -738,29 +736,414 @@ assert(rc == QMCKL_SUCCESS);
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#+end_src
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* Helper Functions
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Private helper-functions that are used by the Sherman-Morrison-Woodbury kernels.
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These functions can only be used internally by the kernels in this module.
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* Sherman-Morrison with update splitting
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** ~qmckl_sherman_morrison_splitting~
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:PROPERTIES:
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:Name: qmckl_sherman_morrison_splitting
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:CRetType: qmckl_exit_code
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:FRetType: qmckl_exit_code
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:END:
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** ~qmckl_slagel_splitting~
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*** Introduction
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This is a variation on the 'Naive' Sherman-Morrison kernel. Whenever the denominator $1+v_j^T S^{-1} u_j$ in
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the Sherman-Morrison formula is deemed to be too close to zero, the update $u_j$ is split in half:
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$u_j \rightarrow \frac{1}{2} u_j$. One half is applied immediately --necessarily increasing the value of the
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denominator because of the split-- while the other halve is put in a queue that will be applied when all the
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remaining updates have been treated.
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The kernel is executed recursively until the queue is eiter empty and all
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updates are applied successfully, or the size of the queue equals the number of initial updates. In the last
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case the Slater-matrix that would have resulted from applying the updates is singular and therefore the
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kernel exits with an exit code.
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If the determinant of the Slater-matrix is passed, it will be updated to the determinant resulting
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from applying the updates to the original matrix.
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*** API
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#+NAME: qmckl_sherman_morrison_splitting_args
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| Variable | Type | In/Out | Description |
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|---------------+-----------------------+--------+------------------------------------------------------|
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| context | qmckl_context | in | Global state |
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| LDS | uint64_t | in | Leading dimension of Slater_inv |
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| Dim | uint64_t | in | Dimension of Slater_inv |
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| N_updates | uint64_t | in | Number of rank-1 updates to be applied to Slater_inv |
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| Updates | double[N_updates*LDS] | in | Array containing the updates |
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| Updates_index | uint64_t[N_updates] | in | Array containing the rank-1 updates |
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| breakdown | double | in | Break-down parameter on which to fail or not |
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| Slater_inv | double[Dim*LDS] | inout | Array containing the inverse of a Slater-matrix |
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| determinant | double | inout | Determinant of the Slater-matrix |
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*** Requirements
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* ~context~ is not ~QMCKL_NULL_CONTEXT~
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* ~LDS >= 2~
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* ~Dim >= 2~
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* ~N_updates >= 1~
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* ~Updates~ is allocated with $N_updates \times Dim$ elements
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* ~Updates_index~ is allocated with $N_updates$ elements
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* ~breakdown~ is a small number such that $0 < breakdown << 1$
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* ~Slater_inv~ is allocated with $Dim \times Dim$ elements
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*** Pedagogical kernel source (in Fortran)
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The following source code written in Fortran is inteded to illustrate how the kernel works. Even though the kernel is
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able to do numerically correct computations, it does not do it in the most efficient way possible. It should therefore
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not be used in real workloads.
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#+begin_src f90 :tangle (eval f)
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integer function qmckl_sherman_morrison_splitting_doc_f(context, &
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lds, dim, &
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nupdates, &
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upds, &
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updates_index, &
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breakdown, &
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s_inv, &
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determinant) result(info)
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use qmckl
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implicit none
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integer*8 , intent(in) :: context
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integer*8 , intent(in) :: lds, dim
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integer*8 , intent(in) :: nupdates
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integer*8 , intent(in) :: updates_index(nupdates)
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real*8 , intent(in) :: upds(nupdates * lds)
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real*8 , intent(in) :: breakdown
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real*8 , intent(inout) :: s_inv(dim * lds)
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real*8 , intent(inout) :: determinant
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real*8 , dimension(lds, nupdates) :: Updates
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real*8 , dimension(dim, lds) :: Inverse
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info = QMCKL_FAILURE
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! Convert 'upds' and 's_inv' into the more easily readable Fortran
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! matrices 'Updates' and 'Inverse'.
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call convert(upds, s_inv, Updates, Inverse, nupdates, lds, dim)
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! YET TO BE IMPLEMENTED
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! Copy updated inverse back to s_inv
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call copy_back(Inverse, s_inv, lds, dim)
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info = QMCKL_SUCCESS
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end function qmckl_sherman_morrison_splitting_doc_f
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#+end_src
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**** C interface to the pedagogical kernel (not directly exposed)
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The following Fortran function ~qmckl_slagel_splitting_doc~ makes sure
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that the pedagogical kernel ~qmckl_slagel_splitting_doc_f~, written in
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Fortran, can be called from C using the ~ISO_C_BINDING~. The Fortran function
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~qmckl_slagel_splitting_doc~ will be exposed in the header file 'qmckl.h'
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for C users and in the module file 'qmckl_f.F90' for Fortran users.
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#+CALL: generate_c_interface(table=qmckl_sherman_morrison_splitting_args,rettyp=get_value("CRetType"),fname="qmckl_sherman_morrison_splitting_doc")
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#+RESULTS:
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#+begin_src f90 :tangle (eval f) :comments org :exports none
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integer(c_int32_t) function qmckl_sherman_morrison_splitting_doc &
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(context, LDS, Dim, N_updates, Updates, Updates_index, breakdown, Slater_inv, determinant) &
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bind(C) result(info)
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use, intrinsic :: iso_c_binding
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implicit none
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integer (c_int64_t) , intent(in) , value :: context
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integer (c_int64_t) , intent(in) , value :: LDS
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integer (c_int64_t) , intent(in) , value :: Dim
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integer (c_int64_t) , intent(in) , value :: N_updates
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real (c_double ) , intent(in) :: Updates(N_updates*LDS)
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integer (c_int64_t) , intent(in) :: Updates_index(N_updates)
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real (c_double ) , intent(in) , value :: breakdown
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real (c_double ) , intent(inout) :: Slater_inv(Dim*LDS)
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real (c_double ) , intent(inout) :: determinant
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integer(c_int32_t), external :: qmckl_sherman_morrison_splitting_doc_f
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info = qmckl_sherman_morrison_splitting_doc_f &
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(context, LDS, Dim, N_updates, Updates, Updates_index, breakdown, Slater_inv, determinant)
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end function qmckl_sherman_morrison_splitting_doc
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#+end_src
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*** C headers (exposed in qmckl.h)
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#+CALL: generate_c_header(table=qmckl_sherman_morrison_splitting_args,rettyp=get_value("CRetType"),fname=get_value("Name"))
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#+RESULTS:
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#+begin_src c :tangle (eval h_func) :comments org
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qmckl_exit_code qmckl_sherman_morrison_splitting (
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const qmckl_context context,
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const uint64_t LDS,
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const uint64_t Dim,
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const uint64_t N_updates,
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const double* Updates,
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const uint64_t* Updates_index,
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const double breakdown,
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double* Slater_inv,
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double* determinant );
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#+end_src
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#+CALL: generate_c_header(table=qmckl_sherman_morrison_splitting_args,rettyp=get_value("CRetType"),fname="qmckl_sherman_morrison_splitting_hpc")
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#+RESULTS:
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#+begin_src c :tangle (eval h_func) :comments org
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qmckl_exit_code qmckl_sherman_morrison_splitting_hpc (
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const qmckl_context context,
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const uint64_t LDS,
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const uint64_t Dim,
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const uint64_t N_updates,
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const double* Updates,
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const uint64_t* Updates_index,
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const double breakdown,
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double* Slater_inv,
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double* determinant );
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#+end_src
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#+CALL: generate_c_header(table=qmckl_sherman_morrison_splitting_args,rettyp=get_value("CRetType"),fname="qmckl_sherman_morrison_splitting_doc")
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#+RESULTS:
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#+begin_src c :tangle (eval h_func) :comments org
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qmckl_exit_code qmckl_sherman_morrison_splitting_doc (
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const qmckl_context context,
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const uint64_t LDS,
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const uint64_t Dim,
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const uint64_t N_updates,
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const double* Updates,
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const uint64_t* Updates_index,
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const double breakdown,
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double* Slater_inv,
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double* determinant );
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#+end_src
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*** C source
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#+begin_src c :tangle (eval c) :comments org
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qmckl_exit_code qmckl_sherman_morrison_splitting_hpc(const qmckl_context context,
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const uint64_t LDS,
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const uint64_t Dim,
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const uint64_t N_updates,
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const double* Updates,
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const uint64_t* Updates_index,
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const double breakdown,
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double* Slater_inv,
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double* determinant) {
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if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
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return qmckl_failwith(context,
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QMCKL_NULL_CONTEXT,
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"qmckl_sherman_morrison_splitting",
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NULL);
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}
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double __attribute__((aligned(8))) later_updates[LDS * N_updates];
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uint64_t later_index[N_updates];
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uint64_t later = 0;
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qmckl_exit_code rc = qmckl_slagel_splitting(
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LDS, Dim, N_updates, Updates, Updates_index, breakdown, Slater_inv,
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later_updates, later_index, &later, determinant);
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if (rc != QMCKL_SUCCESS) return QMCKL_FAILURE;
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if (later > 0) {
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qmckl_exit_code rc = qmckl_sherman_morrison_splitting(
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context, LDS, Dim, later, later_updates, later_index, breakdown,
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Slater_inv, determinant);
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if (rc != QMCKL_SUCCESS) return QMCKL_FAILURE;
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}
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return QMCKL_SUCCESS;
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}
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#+end_src
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#+begin_src c :tangle (eval c) :comments org
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qmckl_exit_code qmckl_sherman_morrison_splitting(const qmckl_context context,
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const uint64_t LDS,
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const uint64_t Dim,
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const uint64_t N_updates,
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const double* Updates,
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const uint64_t* Updates_index,
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const double breakdown,
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double* Slater_inv,
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double* determinant) {
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if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
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return qmckl_failwith(context,
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QMCKL_NULL_CONTEXT,
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"qmckl_sherman_morrison_splitting",
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NULL);
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}
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#ifdef HAS_HPC
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return qmckl_sherman_morrison_splitting_hpc(context,
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LDS,
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Dim,
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N_updates,
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Updates,
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Updates_index,
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breakdown,
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Slater_inv,
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determinant);
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#else
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// return qmckl_sherman_morrison_splitting_doc(context,
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// LDS,
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// Dim,
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// N_updates,
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// Updates,
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// Updates_index,
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// breakdown,
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// Slater_inv,
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// determinant);
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return qmckl_sherman_morrison_splitting_hpc(context,
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LDS,
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Dim,
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N_updates,
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Updates,
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Updates_index,
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breakdown,
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Slater_inv,
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determinant);
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#endif
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return QMCKL_SUCCESS;
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}
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#+end_src
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*** Fortran interfaces (exposed in qmckl_f.F90)
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:PROPERTIES:
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:Name: qmckl_slagel_splitting
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:Name: qmckl_sherman_morrison_naive
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:CRetType: qmckl_exit_code
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:FRetType: qmckl_exit_code
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:END:
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#+CALL: generate_f_interface(table=qmckl_sherman_morrison_splitting_args,rettyp=get_value("FRetType"),fname="qmckl_sherman_morrison_splitting_hpc")
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#+RESULTS:
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#+begin_src f90 :tangle (eval fh_func) :comments org :exports none
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interface
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integer(c_int32_t) function qmckl_sherman_morrison_splitting_hpc &
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(context, LDS, Dim, N_updates, Updates, Updates_index, breakdown, Slater_inv, determinant) &
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bind(C)
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use, intrinsic :: iso_c_binding
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import
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implicit none
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integer (c_int64_t) , intent(in) , value :: context
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integer (c_int64_t) , intent(in) , value :: LDS
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integer (c_int64_t) , intent(in) , value :: Dim
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integer (c_int64_t) , intent(in) , value :: N_updates
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real (c_double ) , intent(in) :: Updates(N_updates*LDS)
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integer (c_int64_t) , intent(in) :: Updates_index(N_updates)
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real (c_double ) , intent(in) , value :: breakdown
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real (c_double ) , intent(inout) :: Slater_inv(Dim*LDS)
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real (c_double ) , intent(inout) :: determinant
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end function qmckl_sherman_morrison_splitting_hpc
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end interface
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#+end_src
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#+CALL: generate_f_interface(table=qmckl_sherman_morrison_splitting_args,rettyp=get_value("FRetType"),fname="qmckl_sherman_morrison_splitting_doc")
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#+RESULTS:
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#+begin_src f90 :tangle (eval fh_func) :comments org :exports none
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interface
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integer(c_int32_t) function qmckl_sherman_morrison_splitting_doc &
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(context, LDS, Dim, N_updates, Updates, Updates_index, breakdown, Slater_inv, determinant) &
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bind(C)
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use, intrinsic :: iso_c_binding
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import
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implicit none
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integer (c_int64_t) , intent(in) , value :: context
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integer (c_int64_t) , intent(in) , value :: LDS
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integer (c_int64_t) , intent(in) , value :: Dim
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integer (c_int64_t) , intent(in) , value :: N_updates
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real (c_double ) , intent(in) :: Updates(N_updates*LDS)
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integer (c_int64_t) , intent(in) :: Updates_index(N_updates)
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real (c_double ) , intent(in) , value :: breakdown
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real (c_double ) , intent(inout) :: Slater_inv(Dim*LDS)
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real (c_double ) , intent(inout) :: determinant
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end function qmckl_sherman_morrison_splitting_doc
|
||||
end interface
|
||||
#+end_src
|
||||
|
||||
#+CALL: generate_f_interface(table=qmckl_sherman_morrison_splitting_args,rettyp=get_value("FRetType"),fname="qmckl_sherman_morrison_splitting")
|
||||
|
||||
#+RESULTS:
|
||||
#+begin_src f90 :tangle (eval fh_func) :comments org :exports none
|
||||
interface
|
||||
integer(c_int32_t) function qmckl_sherman_morrison_splitting &
|
||||
(context, LDS, Dim, N_updates, Updates, Updates_index, breakdown, Slater_inv, determinant) &
|
||||
bind(C)
|
||||
use, intrinsic :: iso_c_binding
|
||||
import
|
||||
implicit none
|
||||
|
||||
integer (c_int64_t) , intent(in) , value :: context
|
||||
integer (c_int64_t) , intent(in) , value :: LDS
|
||||
integer (c_int64_t) , intent(in) , value :: Dim
|
||||
integer (c_int64_t) , intent(in) , value :: N_updates
|
||||
real (c_double ) , intent(in) :: Updates(N_updates*LDS)
|
||||
integer (c_int64_t) , intent(in) :: Updates_index(N_updates)
|
||||
real (c_double ) , intent(in) , value :: breakdown
|
||||
real (c_double ) , intent(inout) :: Slater_inv(Dim*LDS)
|
||||
real (c_double ) , intent(inout) :: determinant
|
||||
|
||||
end function qmckl_sherman_morrison_splitting
|
||||
end interface
|
||||
#+end_src
|
||||
|
||||
*** Performance...
|
||||
This kernel performs best when there are 2 or more rank-1 update cycles and fail-rate is high.
|
||||
|
||||
*** Test
|
||||
#+begin_src c :tangle (eval c_test)
|
||||
assert(Updates3 != NULL);
|
||||
assert(Updates_index3 != NULL);
|
||||
assert(Slater_inv3_2 != NULL);
|
||||
det = -1.23743195512859e-09;
|
||||
rc = qmckl_sherman_morrison_splitting(context, LDS, Dim, N_updates3, Updates3, Updates_index3, breakdown, Slater_inv3_2, &det);
|
||||
assert(fabs(det - 1.602708950725074e-10) < 1e-15);
|
||||
for (unsigned int i = 0; i < Dim; i++) {
|
||||
for (unsigned int j = 0; j < Dim; j++) {
|
||||
res[i * Dim + j] = 0;
|
||||
for (unsigned int k = 0; k < Dim; k++) {
|
||||
res[i * Dim + j] += Slater3[i * Dim + k] * Slater_inv3_2[k * LDS + j];
|
||||
}
|
||||
}
|
||||
}
|
||||
rc = QMCKL_SUCCESS;
|
||||
for (unsigned int i = 0; i < Dim; i++) {
|
||||
for (unsigned int j = 0; j < Dim; j++) {
|
||||
if (i == j && fabs(res[i * Dim + j] - 1) > tolerance) {
|
||||
rc = QMCKL_FAILURE;
|
||||
}
|
||||
if (i != j && fabs(res[i * Dim + j]) > tolerance) {
|
||||
rc = QMCKL_FAILURE;
|
||||
}
|
||||
}
|
||||
}
|
||||
assert(rc == QMCKL_SUCCESS);
|
||||
#+end_src
|
||||
|
||||
|
||||
* Slagel Splitting
|
||||
** ~qmckl_slagel_splitting~
|
||||
:PROPERTIES:
|
||||
:Name: qmckl_slagel_splitting
|
||||
:CRetType: qmckl_exit_code
|
||||
:FRetType: qmckl_exit_code
|
||||
:END:
|
||||
|
||||
*** Introduction
|
||||
~qmckl_slagel_splitting~ is the non-recursive, inner part of the 'Sherman-Morrison with update splitting'-kernel.
|
||||
It is used internally to apply a collection of $N$ rank-1 updates to the inverse Slater-matrix $S^{-1}$ and
|
||||
splitting an update in two equal pieces if necessary. In case of a split, it applies the first half of the update,
|
||||
while putting the second half in a waiting queue to be applied at the end.
|
||||
~qmckl_slagel_splitting~ is the non-recursive, inner part of the 'Sherman-Morrison with update splitting'-kernel.
|
||||
It is used internally to apply a collection of $N$ rank-1 updates to the inverse Slater-matrix $S^{-1}$ and
|
||||
splitting an update in two equal pieces if necessary. In case of a split, it applies the first half of the update,
|
||||
while putting the second half in a waiting queue to be applied at the end.
|
||||
|
||||
Therefore, when $1+v_j^TS^{-1}u_j \geq \epsilon$, the update is applied as usual. Otherwise, $u_j$ will be redefined
|
||||
as $\frac{1}{2}u_j$. One half is applied immediately, the other half will be applied at the end of the algorithm, using vectors
|
||||
$u_{j'}=\frac{1}{2}u_j$ and $v_{j'}^T=v_{j}^T$, which are stored in the array \texttt{later_updates}.
|
||||
Therefore, when $1+v_j^TS^{-1}u_j \geq \epsilon$, the update is applied as usual. Otherwise, $u_j$ will be redefined
|
||||
as $\frac{1}{2}u_j$. One half is applied immediately, the other half will be applied at the end of the algorithm, using vectors
|
||||
$u_{j'}=\frac{1}{2}u_j$ and $v_{j'}^T=v_{j}^T$, which are stored in the array \texttt{later_updates}.
|
||||
|
||||
If the determinant of the Slater-matrix is passed, it will be updated to the determinant resulting
|
||||
from applying the updates to the original matrix.
|
||||
If the determinant of the Slater-matrix is passed, it will be updated to the determinant resulting
|
||||
from applying the updates to the original matrix.
|
||||
|
||||
*** API
|
||||
#+NAME: qmckl_slagel_splitting_args
|
||||
|
|
@ -778,6 +1161,18 @@ These functions can only be used internally by the kernels in this module.
|
|||
| ~later~ | ~uint64_t~ | inout | Number of split updates for later |
|
||||
| ~determinant~ | ~double~ | inout | Determinant of the Slater-matrix |
|
||||
|
||||
*** Requirements
|
||||
* ~LDS >= 2~
|
||||
* ~Dim >= 2~
|
||||
* ~N_updates >= 1~
|
||||
* ~Updates~ is allocated with $N_updates \times Dim$ elements
|
||||
* ~Updates_index~ is allocated with $N_updates$ elements
|
||||
* ~breakdown~ is a small number such that $0 < breakdown << 1$
|
||||
* ~Slater_inv~ is allocated with $Dim \times Dim$ elements
|
||||
* ~later_updates~ is allocated with $later \times Dim$ elements
|
||||
* ~later_index~ is allocated with $N_updates$ elements
|
||||
* ~later >= 0~
|
||||
|
||||
*** Pedagogical kernel source (in Fortran)
|
||||
The following source code written in Fortran is inteded to illustrate how the kernel works. Even though the kernel is
|
||||
able to do numerically correct computations, it does not do it in the most efficient way possible. It should therefore
|
||||
|
|
@ -885,20 +1280,7 @@ integer(c_int32_t) function qmckl_slagel_splitting_doc &
|
|||
end function qmckl_slagel_splitting_doc
|
||||
#+end_src
|
||||
|
||||
*** Requirements
|
||||
* ~LDS >= 2~
|
||||
* ~Dim >= 2~
|
||||
* ~N_updates >= 1~
|
||||
* ~Updates~ is allocated with $N_updates \times Dim$ elements
|
||||
* ~Updates_index~ is allocated with $N_updates$ elements
|
||||
* ~breakdown~ is a small number such that $0 < breakdown << 1$
|
||||
* ~Slater_inv~ is allocated with $Dim \times Dim$ elements
|
||||
* ~later_updates~ is allocated with $later \times Dim$ elements
|
||||
* ~later_index~ is allocated with $N_updates$ elements
|
||||
* ~later >= 0~
|
||||
|
||||
*** C headers (exposed in qmckl.h)
|
||||
|
||||
#+CALL: generate_c_header(table=qmckl_slagel_splitting_args,rettyp=get_value("CRetType"),fname=get_value("Name"))
|
||||
|
||||
#+RESULTS:
|
||||
|
|
@ -1175,11 +1557,11 @@ qmckl_exit_code qmckl_slagel_splitting(
|
|||
#+end_src
|
||||
|
||||
*** Fortran interfaces (exposed in qmckl_f.F90)
|
||||
:PROPERTIES:
|
||||
:Name: qmckl_slagel_splitting
|
||||
:CRetType: qmckl_exit_code
|
||||
:FRetType: qmckl_exit_code
|
||||
:END:
|
||||
:PROPERTIES:
|
||||
:Name: qmckl_slagel_splitting
|
||||
:CRetType: qmckl_exit_code
|
||||
:FRetType: qmckl_exit_code
|
||||
:END:
|
||||
|
||||
#+CALL: generate_f_interface(table=qmckl_slagel_splitting_args,rettyp=get_value("FRetType"),fname="qmckl_slagel_splitting_hpc")
|
||||
|
||||
|
|
|
|||
Loading…
Reference in New Issue
Block a user