Added missing C test program

test/c_test_programs/elpa2_test_real_c_version.c

+/*     This file is part of ELPA. */
+/*  */
+/*     The ELPA library was originally created by the ELPA consortium, */
+/*     consisting of the following organizations: */
+/*  */
+/*     - Rechenzentrum Garching der Max-Planck-Gesellschaft (RZG), */
+/*     - Bergische Universität Wuppertal, Lehrstuhl für angewandte */
+/*       Informatik, */
+/*     - Technische Universität München, Lehrstuhl für Informatik mit */
+/*       Schwerpunkt Wissenschaftliches Rechnen , */
+/*     - Fritz-Haber-Institut, Berlin, Abt. Theorie, */
+/*     - Max-Plack-Institut für Mathematik in den Naturwissenschaften, */
+/*       Leipzig, Abt. Komplexe Strukutren in Biologie und Kognition, */
+/*       and */
+/*     - IBM Deutschland GmbH */
+/*  */
+/*  */
+/*     More information can be found here: */
+/*     http://elpa.rzg.mpg.de/ */
+/*  */
+/*     ELPA is free software: you can redistribute it and/or modify */
+/*     it under the terms of the version 3 of the license of the */
+/*     GNU Lesser General Public License as published by the Free */
+/*     Software Foundation. */
+/*  */
+/*     ELPA is distributed in the hope that it will be useful, */
+/*     but WITHOUT ANY WARRANTY; without even the implied warranty of */
+/*     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the */
+/*     GNU Lesser General Public License for more details. */
+/*  */
+/*     You should have received a copy of the GNU Lesser General Public License */
+/*     along with ELPA.  If not, see <http://www.gnu.org/licenses/> */
+/*  */
+/*     ELPA reflects a substantial effort on the part of the original */
+/*     ELPA consortium, and we ask you to respect the spirit of the */
+/*     license that we chose: i.e., please contribute any changes you */
+/*     may have back to the original ELPA library distribution, and keep */
+/*     any derivatives of ELPA under the same license that we chose for */
+/*     the original distribution, the GNU Lesser General Public License. */
+/*  */
+/*  */
+
+#include "config-f90.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <mpi.h>
+#include <math.h>
+
+#include <elpa/elpa.h>
+
+main(int argc, char** argv) {
+   int myid;
+   int nprocs;
+
+   int na, nev, nblk;
+
+   int status;
+
+   int np_cols, np_rows, np_colsStart;
+
+   int my_blacs_ctxt, nprow, npcol, my_prow, my_pcol;
+
+   int mpierr;
+
+   int my_mpi_comm_world;
+   int mpi_comm_rows, mpi_comm_cols;
+
+   int info, *sc_desc;
+
+   int na_rows, na_cols;
+   double startVal;
+
+   double *a, *z, *as, *ev, *tmp1, *tmp2;
+
+   int *iseed;
+
+   int success;
+
+   int useQr, THIS_REAL_ELPA_KERNEL_API;
+
+   MPI_Init(&argc, &argv);
+   MPI_Comm_size(MPI_COMM_WORLD, &nprocs);
+   MPI_Comm_rank(MPI_COMM_WORLD, &myid);
+
+   na = 1000;
+   nev = 500;
+   nblk = 16;
+
+   if (myid == 0) {
+     printf("This is the c version of an ELPA test-programm\n");
+     printf("\n");
+     printf("It will call the 1stage ELPA real solver for an\n");
+     printf("of matrix size %d. It will compute %d eigenvalues\n",na,nev);
+     printf("and uses a blocksize of %d\n",nblk);
+     printf("\n");
+     printf("This is an example program with much less functionality\n");
+     printf("as it's Fortran counterpart. It's only purpose is to show how \n");
+     printf("to evoke ELPA1 from a c programm\n");
+     printf("\n");
+
+   }
+
+   status = 0;
+
+   startVal = sqrt((double) nprocs);
+   np_colsStart = (int) round(startVal);
+   for (np_cols=np_colsStart;np_cols>1;np_cols--){
+     if (nprocs %np_cols ==0){
+     break;
+     }
+   }
+
+   np_rows = nprocs/np_cols;
+
+   if (myid == 0) {
+     printf("\n");
+     printf("Number of processor rows %d, cols %d, total %d \n",np_rows,np_cols,nprocs);
+   }
+
+   /* set up blacs */
+   /* convert communicators before */
+   my_mpi_comm_world = MPI_Comm_c2f(MPI_COMM_WORLD);
+   set_up_blacsgrid_from_fortran(my_mpi_comm_world, &my_blacs_ctxt, &np_rows, &np_cols, &nprow, &npcol, &my_prow, &my_pcol);
+
+   if (myid == 0) {
+     printf("\n");
+     printf("Past BLACS_Gridinfo...\n");
+     printf("\n");
+   }
+
+   /* get the ELPA row and col communicators. */
+   /* These are NOT usable in C without calling the MPI_Comm_f2c function on them !! */
+   my_mpi_comm_world = MPI_Comm_c2f(MPI_COMM_WORLD);
+   mpierr = elpa_get_communicators(my_mpi_comm_world, my_prow, my_pcol, &mpi_comm_rows, &mpi_comm_cols);
+
+   if (myid == 0) {
+     printf("\n");
+     printf("Past split communicator setup for rows and columns...\n");
+     printf("\n");
+   }
+
+   sc_desc = malloc(9*sizeof(int));
+
+   set_up_blacs_descriptor_from_fortran(na, nblk, my_prow, my_pcol, np_rows, np_cols, &na_rows, &na_cols, sc_desc, my_blacs_ctxt, &info);
+
+   if (myid == 0) {
+     printf("\n");
+     printf("Past scalapack descriptor setup...\n");
+     printf("\n");
+   }
+
+   /* allocate the matrices needed for elpa */
+   if (myid == 0) {
+     printf("\n");
+     printf("Allocating matrices with na_rows=%d and na_cols=%d\n",na_rows, na_cols);
+     printf("\n");
+   }
+
+   a  = malloc(na_rows*na_cols*sizeof(double));
+   z  = malloc(na_rows*na_cols*sizeof(double));
+   as = malloc(na_rows*na_cols*sizeof(double));
+
+
+   ev = malloc(na*sizeof(double));
+
+   tmp1  = malloc(na_rows*na_cols*sizeof(double));
+   tmp2 = malloc(na_rows*na_cols*sizeof(double));
+
+   iseed = malloc(4096*sizeof(int));
+
+   prepare_matrix_real_from_fortran(na, myid, na_rows, na_cols, sc_desc, iseed, a, z, as);
+
+   if (myid == 0) {
+     printf("\n");
+     printf("Entering ELPA 2stage real solver\n");
+     printf("\n");
+   }
+
+   mpierr = MPI_Barrier(MPI_COMM_WORLD);
+   useQr = 0;
+   THIS_REAL_ELPA_KERNEL_API = ELPA2_REAL_KERNEL_GENERIC;
+
+   success = elpa_solve_evp_real_2stage(na, nev, a, na_rows, ev, z, na_rows, nblk, na_cols, mpi_comm_rows, mpi_comm_cols, my_mpi_comm_world, THIS_REAL_ELPA_KERNEL_API, useQr);
+
+   if (success != 1) {
+     printf("error in ELPA solve \n");
+     mpierr = MPI_Abort(MPI_COMM_WORLD, 99);
+   }
+
+
+   if (myid == 0) {
+     printf("\n");
+     printf("2stage ELPA real solver complete\n");
+     printf("\n");
+   }
+
+   /* check the results */
+   status = check_correctness_real_from_fortran(na, nev, na_rows, na_cols, as, z, ev, sc_desc, myid, tmp1, tmp2);
+
+   if (status !=0){
+     printf("The computed EVs are not correct !\n");
+   }
+   if (status ==0){
+     if (myid ==0) {
+       printf("All ok!\n");
+     }
+   }
+
+   free(sc_desc);
+   free(a);
+   free(z);
+   free(as);
+
+   free(tmp1);
+   free(tmp2);
+
+   MPI_Finalize();
+
+   return 0;
+}