1elpa_get_communicators(3)  Library Functions Manual  elpa_get_communicators(3)
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NAME

6       elpa_get_communicators
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SYNOPSIS

10   FORTRAN INTERFACE
11       use elpa1
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13       success = elpa_get_communicators (mpi_comm_global, my_prow, my_pcol,
14       mpi_comm_rows, mpi_comm_cols)
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16       integer, intent(in)   mpi_comm_global:  global communicator for the
17       calculation
18       integer, intent(in)   my_prow:          row coordinate of the calling
19       process in the process grid
20       integer, intent(in)   my_pcol:          column coordinate of the
21       calling process in the process grid
22       integer, intent(out)  mpi_comm_row:     communicator for communication
23       within rows of processes
24       integer, intent(out)  mpi_comm_row:     communicator for communication
25       within columns of processes
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27       integer               success:          return value indicating success
28       or failure of the underlying MPI_COMM_SPLIT function
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31   C INTERFACE
32       #include "elpa_generated.h"
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34       success = elpa_get_communicators (int mpi_comm_world, int my_prow,
35       my_pcol, int *mpi_comm_rows, int *Pmpi_comm_cols);
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37       int mpi_comm_global:  global communicator for the calculation
38       int my_prow:          row coordinate of the calling process in the
39       process grid
40       int my_pcol:          column coordinate of the calling process in the
41       process grid
42       int *mpi_comm_row:    pointer to the communicator for communication
43       within rows of processes
44       int *mpi_comm_row:    pointer to the communicator for communication
45       within columns of processes
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47       int  success:         return value indicating success or failure of the
48       underlying MPI_COMM_SPLIT function
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DESCRIPTION

55       All ELPA routines need MPI communicators for communicating within rows
56       or columns of processes. These communicators are created from the
57       mpi_comm_global communicator. It is assumed that the matrix used in
58       ELPA is distributed with my_prow rows and my_pcol columns on the
59       calling process. This function has to be envoked by all involved
60       processes before any other calls to ELPA routines.
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SEE ALSO

63       elpa_get_communicators(3) elpa_solve_evp_real(3)
64       elpa_solve_evp_complex(3) elpa2_print_kernels(1)
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68ELPA                            Tue Nov 28 2017      elpa_get_communicators(3)
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