MPI_Intercomm_merge(3)

1MPI_Intercomm_merge(3)              LAM/MPI             MPI_Intercomm_merge(3)
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NAME

6       MPI_Intercomm_merge  -  Creates an intracommuncator from an intercommu‐
7       nicator
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SYNOPSIS

10       #include <mpi.h>
11       int MPI_Intercomm_merge(MPI_Comm comm, int high,
12                             MPI_Comm *newcomm)
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INPUT PARAMETERS

15       comm   - Intercommunicator
16       high   - Used to order the groups of the two intracommunicators  within
17              comm when creating the new communicator.
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OUTPUT PARAMETER

21       newcomm
22              - Created intracommunicator
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NOTES FOR FORTRAN

26       All  MPI routines in Fortran (except for MPI_WTIME and MPI_WTICK ) have
27       an additional argument ierr at the end of the argument list.   ierr  is
28       an  integer and has the same meaning as the return value of the routine
29       in C.  In Fortran, MPI routines are subroutines, and are  invoked  with
30       the call statement.
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32       All MPI objects (e.g., MPI_Datatype , MPI_Comm ) are of type INTEGER in
33       Fortran.
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ERRORS

37       If an error occurs in an MPI function, the current MPI error handler is
38       called  to  handle  it.   By default, this error handler aborts the MPI
39       job.  The error handler may be changed with  MPI_Errhandler_set  ;  the
40       predefined  error  handler MPI_ERRORS_RETURN may be used to cause error
41       values to be returned (in C and Fortran; this  error  handler  is  less
42       useful  in  with  the  C++  MPI bindings.  The predefined error handler
43       MPI::ERRORS_THROW_EXCEPTIONS should be used in C++ if the  error  value
44       needs  to  be recovered).  Note that MPI does not guarantee that an MPI
45       program can continue past an error.
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47       All MPI routines (except MPI_Wtime and  MPI_Wtick  )  return  an  error
48       value;  C routines as the value of the function and Fortran routines in
49       the last argument.  The C++ bindings for MPI do not return  error  val‐
50       ues;  instead,  error values are communicated by throwing exceptions of
51       type MPI::Exception (but not by default).  Exceptions are  only  thrown
52       if the error value is not MPI::SUCCESS .
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55       Note  that  if  the MPI::ERRORS_RETURN handler is set in C++, while MPI
56       functions will return upon an error, there will be no  way  to  recover
57       what the actual error value was.
58       MPI_SUCCESS
59              - No error; MPI routine completed successfully.
60       MPI_ERR_COMM
61              -  Invalid communicator.  A common error is to use a null commu‐
62              nicator in a call (not even allowed in MPI_Comm_rank ).
63       MPI_ERR_ARG
64              - Invalid argument.  Some argument is invalid and is not identi‐
65              fied  by  a  specific  error  class.   This  is typically a NULL
66              pointer or other such error.
67       MPI_ERR_OTHER
68              - This error is returned when some part of the LAM/MPI implemen‐
69              tation is unable to acquire memory.
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MORE INFORMATION

77       For more information, please see the official MPI Forum web site, which
78       contains the text of both the MPI-1 and MPI-2 standards.   These  docu‐
79       ments  contain  detailed  information  about each MPI function (most of
80       which is not duplicated in these man pages).
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82       http://www.mpi-forum.org/
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ACKNOWLEDGEMENTS

87       The LAM Team would like the thank the MPICH Team for the handy  program
88       to  generate  man  pages ("doctext" from ftp://ftp.mcs.anl.gov/pub/sow‐
89       ing/sowing.tar.gz ), the initial formatting, and some initial text  for
90       most of the MPI-1 man pages.
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LOCATION

93       icmerge.c
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97LAM/MPI 7.1.2                      2/23/2006            MPI_Intercomm_merge(3)