From 3f6bca2b049df7844e8a75ffe7ef98dc40db4a60 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Fran=C3=A7ois=20Coppens?= Date: Sat, 6 Feb 2021 18:59:07 +0100 Subject: [PATCH] The Fortran interface to C++ fuction MaponiA3() works but the mechanism of passing the 2D arrays from Fortran to C++ must be improved. Now the passed 'linear' 2D arrays are copied and reshaped into usable 2D arrays. This needs to be replaced with some suitable casting mechanism. --- Helpers.hpp | 17 ++++++ Makefile | 2 +- SM_MaponiA3.hpp | 5 +- SM_MaponiA3_f.cpp | 145 ++++++++++++++++++++++++++++++++++++++++++++ SM_MaponiA3_f.hpp | 4 ++ SM_MaponiA3_mod.f90 | 8 +-- fmain.f90 | 18 +++--- mwe/main.cpp | 23 +++++++ 8 files changed, 204 insertions(+), 18 deletions(-) create mode 100644 SM_MaponiA3_f.cpp create mode 100644 SM_MaponiA3_f.hpp create mode 100644 mwe/main.cpp diff --git a/Helpers.hpp b/Helpers.hpp index 646ba6e..23bf812 100644 --- a/Helpers.hpp +++ b/Helpers.hpp @@ -75,6 +75,23 @@ T **matMul(T **A, T **B, unsigned int size) { return C; } +template +T **matMul2(T **A, T (*B)[], unsigned int size) { + T **C = new T*[size]; + for (unsigned int i = 0; i < size; i++) { + C[i] = new T[size]; + } + for (unsigned int i = 0; i < size; i++) { + for (unsigned int j = 0; j < size; j++) { + for (unsigned int k = 0; k < size; k++) { + C[i][j] += A[i][k] * B[k][j]; + } + } + } + return C; +} + + template T1 **outProd(T1 *vec1, T2 *vec2, unsigned int size) { T1 **C = new T1*[size]; diff --git a/Makefile b/Makefile index 842dbbe..1a51821 100644 --- a/Makefile +++ b/Makefile @@ -13,7 +13,7 @@ cppOBJ = cppmain.o SM_MaponiA3.o ## Deps & objs for the Fortran stuff fDEPS = fmain.f90 SM_MaponiA3_mod.f90 -fOBJ = SM_MaponiA3.o SM_MaponiA3_mod.o fmain.o +fOBJ = SM_MaponiA3_f.o SM_MaponiA3_mod.o fmain.o fLIBS = -lstdc++ ## Compile recipes for C++ stuff diff --git a/SM_MaponiA3.hpp b/SM_MaponiA3.hpp index 0a53741..5e330ba 100644 --- a/SM_MaponiA3.hpp +++ b/SM_MaponiA3.hpp @@ -1,5 +1,2 @@ // SM-MaponiA3.hpp -extern "C" { - void Sherman_Morrison(int **Slater0, double **Slater_inv, unsigned int *Dim, unsigned int *N_updates, int **Updates, unsigned int *Updates_index); -} - +void Sherman_Morrison(int **Slater0, double **Slater_inv, unsigned int *Dim, unsigned int *N_updates, int **Updates, unsigned int *Updates_index); diff --git a/SM_MaponiA3_f.cpp b/SM_MaponiA3_f.cpp new file mode 100644 index 0000000..e56e1fb --- /dev/null +++ b/SM_MaponiA3_f.cpp @@ -0,0 +1,145 @@ +// SM-MaponiA3_f.cpp +// Algorithm 3 from P. Maponi, +// p. 283, doi:10.1016/j.laa.2006.07.007 +#include "SM_MaponiA3_f.hpp" +#include "Helpers.hpp" + +void MaponiA3(int **linSlater0, double **linSlater_inv, unsigned int *Dim, unsigned int *N_updates, int **linUpdates, unsigned int *Updates_index) { + + // Define new 2D arrays and copy the elements of the + // linear passed Fortran arrays. This block needs to + // be replaced with some casting mechanism to avoid + // copying of arrays. + int **Slater0 = new int*[*Dim]; + int **Updates = new int*[*Dim]; + double **Slater_inv = new double*[*Dim]; + for (int i = 0; i < *Dim; i++) { + Slater0[i] = new int[*Dim]; + Updates[i] = new int[*Dim]; + Slater_inv[i] = new double[*Dim]; + } + for (unsigned int i = 0; i < *Dim; i++) { + for (unsigned int j = 0; j < *Dim; j++) { + Slater0[i][j] = linSlater0[0][i+*Dim*j]; + Slater_inv[i][j] = linSlater_inv[0][i+*Dim*j]; + Updates[i][j] = linUpdates[0][i+*Dim*j]; + } + } + + // Possible casting candidates + // int (*Slater0)[*Dim] = (int(*)[*Dim])linSlater0[0]; + // double (*Slater_inv)[*Dim] = (double(*)[*Dim])linSlater_inv[0]; + // int (*Updates)[*Dim] = (int(*)[*Dim])linUpdates[0]; + //////////////////////////////////////////////////////////////////////// + + unsigned int k, l, lbar, i, j, tmp, M = *Dim; + unsigned int *p = new unsigned int[M+1]; + unsigned int **Id = new unsigned int*[M]; + double alpha, beta; + double **U, *breakdown = new double[M+1]; + double **Al = new double*[M]; + p[0] = 0; + for (i = 0; i < M; i++) { + p[i+1] = i + 1; + Id[i] = new unsigned int[M]; + Al[i] = new double[M]; + } + + // Declare auxiliary solution matrix ylk + double ***ylk = new double**[M]; + for (l = 0; l < M; l++) { + ylk[l] = new double*[M+1]; + for (k = 0; k < M+1; k++) { + ylk[l][k] = new double[M+1]; + } + } + + // Initialize identity matrix + for (i = 0; i < M; i++) { + for (j = 0; j < M; j++) { + if (i != j) Id[i][j] = 0; + else Id[i][j] = 1; + } + } + + // Initialize ylk with zeros + for (l = 0; l < M; l++) { + for (k = 0; k < M+1; k++) { + for (i = 0; i < M+1; i++) { + ylk[l][k][i] = 0; + } + } + } + + // Calculate all the y0k in M^2 multiplications instead of M^3 + for (k = 1; k < M+1; k++) { + for (i = 1; i < M+1; i++) { + ylk[0][k][i] = Slater_inv[i-1][i-1] * Updates[i-1][k-1]; + } + } + + // Calculate all the ylk from the y0k + for (l = 1; l < M; l++) { + for (j = l; j < M+1; j++) { + breakdown[j] = abs( 1 + ylk[l-1][p[j]][p[j]] ); + } + lbar = getMaxIndex(breakdown, M+1); + for (i = 0; i < M; i++) { + breakdown[i] = 0; + } + tmp = p[l]; + p[l] = p[lbar]; + p[lbar] = tmp; + for (k = l+1; k < M+1; k++) { + beta = 1 + ylk[l-1][p[l]][p[l]]; + if (beta == 0) { + cout << "Break-down condition occured. Exiting..." << endl; + exit; + } + for (i = 1; i < M+1; i++) { + alpha = ylk[l-1][p[k]][p[l]] / beta; + ylk[l][p[k]][i] = ylk[l-1][p[k]][i] - alpha * ylk[l-1][p[l]][i]; + } + } + } + + // Construct A-inverse from A0-inverse and the ylk + // Keep the memory location of the passed array 'Slater_inv' before 'Slater_inv' + // gets reassigned by 'matMul(...)' in the next line, by creating a new + // pointer 'copy' that points to whereever 'Slater_inv' points to now. + // double **copy = Slater_inv; + + for (l = 0; l < M; l++) { + k = l+1; + U = outProd(ylk[l][p[k]], Id[p[k]-1], M); + beta = 1 + ylk[l][p[k]][p[k]]; + for (i = 0; i < M; i++) { + for (j = 0; j < M; j++) { + Al[i][j] = Id[i][j] - U[i][j] / beta; + } + } + Slater_inv = matMul(Al, Slater_inv, M); + } + + // // Assign the new values of 'Slater_inv' to the old values in 'copy[][]' + // for (i = 0; i < M; i++) { + // for (j = 0; j < M; j++) { + // copy[i][j] = Slater_inv[i][j]; + // } + // } + + // Assign the new values of 'Slater_inv' to the old values in 'copy[][]' + for (i = 0; i < M; i++) { + for (j = 0; j < M; j++) { + linSlater_inv[0][i+*Dim*j] = Slater_inv[i][j]; + } + } + + for (l = 0; l < M; l++) { + for (k = 0; k < M+1; k++) { + delete [] ylk[l][k]; + } + delete [] ylk[l], Id[l], U[l], Al[l], Slater_inv[l]; + } + delete [] p, breakdown; +} \ No newline at end of file diff --git a/SM_MaponiA3_f.hpp b/SM_MaponiA3_f.hpp new file mode 100644 index 0000000..1537a65 --- /dev/null +++ b/SM_MaponiA3_f.hpp @@ -0,0 +1,4 @@ +// SM-MaponiA3_f.hpp +extern "C" { + void MaponiA3(int **linSlater0, double **linSlater_inv, unsigned int *Dim, unsigned int *N_updates, int **linUpdates, unsigned int *Updates_index); +} diff --git a/SM_MaponiA3_mod.f90 b/SM_MaponiA3_mod.f90 index c1d9e91..1708fd0 100644 --- a/SM_MaponiA3_mod.f90 +++ b/SM_MaponiA3_mod.f90 @@ -1,11 +1,11 @@ -module MYMODULE +module Sherman_Morrison interface - subroutine MYSUBROUTINE(Slater0, Slater_inv, dim, n_updates, Updates, Updates_index) bind(C, name="Sherman_Morrison") + subroutine MaponiA3(Slater0, Slater_inv, dim, n_updates, Updates, Updates_index) bind(C, name="MaponiA3") use, intrinsic :: iso_c_binding, only : c_int, c_double integer(c_int), intent(in) :: dim, n_updates integer(c_int), dimension(:), allocatable, intent(in) :: Updates_index integer(c_int), dimension(:,:), allocatable, intent(in) :: Slater0, Updates real(c_double), dimension(:,:), allocatable, intent(in out) :: Slater_inv - end subroutine MYSUBROUTINE + end subroutine MaponiA3 end interface -end module MYMODULE \ No newline at end of file +end module Sherman_Morrison \ No newline at end of file diff --git a/fmain.f90 b/fmain.f90 index fe6447f..447ee46 100644 --- a/fmain.f90 +++ b/fmain.f90 @@ -1,6 +1,6 @@ program Interface_test + use Sherman_Morrison, only : MaponiA3 use, intrinsic :: iso_c_binding, only : c_int, c_double - use MYMODULE, only : MYSUBROUTINE implicit none integer i, j !! Iterators @@ -38,15 +38,15 @@ program Interface_test Ar(i,j) = A(i,j) - A0(i,j) end do end do + + call MaponiA3(A0, A0_inv, dim, n_updates, Ar, Ar_index) - ! do i=1,dim - ! do j=1,dim - ! write(*,"(I)", advance="no") Ar_index(i) - ! end do - ! write(*,*) - ! end do - - call MYSUBROUTINE(A0, A0_inv, dim, n_updates, Ar, Ar_index) + do i=1,dim + do j=1,dim + write(*,"(F3.0,3X)", advance="no") A0_inv(i,j) + end do + write(*,*) + end do deallocate(Ar_index, A, A0, Ar, A0_inv) end program diff --git a/mwe/main.cpp b/mwe/main.cpp new file mode 100644 index 0000000..cdf7867 --- /dev/null +++ b/mwe/main.cpp @@ -0,0 +1,23 @@ +#include + + +int main() +{ + + typedef int (*to2D)[3]; //pint2 is a pointer to an array of 2 ints + int linArray[9] = {0,1,2,3,4,5,6,7,8}; + + to2D dArray = (to2D)linArray; + + std::cout << dArray[0][0] << std::endl; + std::cout << dArray[0][1] << std::endl; + std::cout << dArray[0][2] << std::endl; + std::cout << dArray[1][0] << std::endl; + std::cout << dArray[1][1] << std::endl; + std::cout << dArray[1][2] << std::endl; + std::cout << dArray[2][0] << std::endl; + std::cout << dArray[2][1] << std::endl; + std::cout << dArray[2][2] << std::endl; + + return 0; +}