1MPI_Scatterv(3) LAM/MPI MPI_Scatterv(3)
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6 MPI_Scatterv - Scatters a buffer in parts to all tasks in a group
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9 #include <mpi.h>
10 int MPI_Scatterv(void *sbuf, int *scounts, int *disps,
11 MPI_Datatype sdtype, void* rbuf, int rcount,
12 MPI_Datatype rdtype, int root, MPI_Comm comm)
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15 sbuf - address of send buffer (choice, significant only at root )
16 scounts
17 - integer array (of length group size) specifying the number of
18 elements to send to each processor
19 disps - integer array (of length group size). Entry i specifies the
20 displacement (relative to sendbuf from which to take the outgo‐
21 ing data to process i
22 sdtype - data type of send buffer elements (handle)
24 rcount - number of elements in receive buffer (integer)
25 rtype - data type of receive buffer elements (handle)
26 root - rank of sending process (integer)
27 comm - communicator (handle)
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31 rbuf - address of receive buffer (choice)
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35 All MPI routines in Fortran (except for MPI_WTIME and MPI_WTICK ) have
36 an additional argument ierr at the end of the argument list. ierr is
37 an integer and has the same meaning as the return value of the routine
38 in C. In Fortran, MPI routines are subroutines, and are invoked with
39 the call statement.
40 All MPI objects (e.g., MPI_Datatype , MPI_Comm ) are of type INTEGER in
42 Fortran.
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46 If an error occurs in an MPI function, the current MPI error handler is
47 called to handle it. By default, this error handler aborts the MPI
48 job. The error handler may be changed with MPI_Errhandler_set ; the
49 predefined error handler MPI_ERRORS_RETURN may be used to cause error
50 values to be returned (in C and Fortran; this error handler is less
51 useful in with the C++ MPI bindings. The predefined error handler
52 MPI::ERRORS_THROW_EXCEPTIONS should be used in C++ if the error value
53 needs to be recovered). Note that MPI does not guarantee that an MPI
54 program can continue past an error.
55 All MPI routines (except MPI_Wtime and MPI_Wtick ) return an error
57 value; C routines as the value of the function and Fortran routines in
58 the last argument. The C++ bindings for MPI do not return error val‐
59 ues; instead, error values are communicated by throwing exceptions of
60 type MPI::Exception (but not by default). Exceptions are only thrown
61 if the error value is not MPI::SUCCESS .
62 Note that if the MPI::ERRORS_RETURN handler is set in C++, while MPI
65 functions will return upon an error, there will be no way to recover
66 what the actual error value was.
67 MPI_SUCCESS
68 - No error; MPI routine completed successfully.
69 MPI_ERR_COMM
70 - Invalid communicator. A common error is to use a null commu‐
71 nicator in a call (not even allowed in MPI_Comm_rank ).
72 MPI_ERR_OTHER
73 - A collective implementation was not able to be located at run-
74 time for this communicator.
75 MPI_ERR_OTHER
76 - A communicator that contains some non-local IMPI procs was
77 used for some function which has not yet had the IMPI extensions
78 implemented yet. For example, most collectives on IMPI communi‐
79 cators have not been implemented yet.
80 MPI_ERR_COUNT
81 - Invalid count argument. Count arguments must be non-negative;
82 a count of zero is often valid.
83 MPI_ERR_TYPE
84 - Invalid datatype argument. May be an uncommitted MPI_Datatype
85 (see MPI_Type_commit ).
86 MPI_ERR_BUFFER
87 - Invalid buffer pointer. Usually a null buffer where one is
88 not valid.
89 MPI_ERR_ROOT
90 - Invalid root. The root must be specified as a rank in the
91 communicator. Ranks must be between zero and the size of the
92 communicator minus one.
93 MPI_ERR_ARG
94 - Invalid argument. Some argument is invalid and is not identi‐
95 fied by a specific error class. This is typically a NULL
96 pointer or other such error.
97
100 For more information, please see the official MPI Forum web site, which
101 contains the text of both the MPI-1 and MPI-2 standards. These docu‐
102 ments contain detailed information about each MPI function (most of
103 which is not duplicated in these man pages).
104 http://www.mpi-forum.org/
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110 The LAM Team would like the thank the MPICH Team for the handy program
111 to generate man pages ("doctext" from ftp://ftp.mcs.anl.gov/pub/sow‐
112 ing/sowing.tar.gz ), the initial formatting, and some initial text for
113 most of the MPI-1 man pages.
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116 scatterv.c
117LAM/MPI 7.1.2 2/23/2006 MPI_Scatterv(3)