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MPI_Type_hindexed

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Creates an indexed datatype with offsets in bytes 
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Synopsis

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int MPI_Type_hindexed(int count,
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                      int *array_of_blocklengths,
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                      MPI_Aint * array_of_displacements,
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                      MPI_Datatype oldtype, MPI_Datatype * newtype)
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Input Parameters

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count
number of blocks -- also number of entries in array_of_displacements and array_of_blocklengths
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array_of_blocklengths
number of elements in each block (array of nonnegative integers)
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array_of_displacements
byte displacement of each block (array of MPI_Aint)
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oldtype
old datatype (handle)
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Output Parameters

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newtype
new datatype (handle)
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Deprecated Function

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The MPI-2 standard deprecated a number of routines because MPI-2 provides
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better versions.  This routine is one of those that was deprecated.  The
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routine may continue to be used, but new code should use the replacement
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routine.
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This routine is replaced by <tt>MPI_Type_create_hindexed</tt>.
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Thread and Interrupt Safety

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This routine is thread-safe.  This means that this routine may be
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safely used by multiple threads without the need for any user-provided
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thread locks.  However, the routine is not interrupt safe.  Typically,
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this is due to the use of memory allocation routines such as <tt>malloc
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</tt>or other non-MPICH runtime routines that are themselves not interrupt-safe.
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Notes for Fortran

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All MPI routines in Fortran (except for <tt>MPI_WTIME</tt> and <tt>MPI_WTICK</tt>) have
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an additional argument <tt>ierr</tt> at the end of the argument list.  <tt>ierr
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</tt>is an integer and has the same meaning as the return value of the routine
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in C.  In Fortran, MPI routines are subroutines, and are invoked with the
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<tt>call</tt> statement.
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All MPI objects (e.g., <tt>MPI_Datatype</tt>, <tt>MPI_Comm</tt>) are of type <tt>INTEGER
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</tt>in Fortran.
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The array_of_displacements are displacements, and are based on a zero origin.  A common error
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is to do something like to following
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    integer a(100)
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    integer array_of_blocklengths(10), array_of_displacements(10)
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    do i=1,10
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         array_of_blocklengths(i)   = 1
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10       array_of_displacements(i) = (1 + (i-1)*10) * sizeofint
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    call MPI_TYPE_HINDEXED(10,array_of_blocklengths,array_of_displacements,MPI_INTEGER,newtype,ierr)
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    call MPI_TYPE_COMMIT(newtype,ierr)
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    call MPI_SEND(a,1,newtype,...)
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expecting this to send "a(1),a(11),..." because the array_of_displacements have values
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"1,11,...".   Because these are displacements from the beginning of "a",
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it actually sends "a(1+1),a(1+11),...".
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If you wish to consider the displacements as array_of_displacements into a Fortran array,
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consider declaring the Fortran array with a zero origin
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    integer a(0:99)
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Errors

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All MPI routines (except <tt>MPI_Wtime</tt> and <tt>MPI_Wtick</tt>) return an error value;
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C routines as the value of the function and Fortran routines in the last
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argument.  Before the value is returned, the current MPI error handler is
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called.  By default, this error handler aborts the MPI job.  The error handler
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may be changed with <tt>MPI_Comm_set_errhandler</tt> (for communicators),
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<tt>MPI_File_set_errhandler</tt> (for files), and <tt>MPI_Win_set_errhandler</tt> (for
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RMA windows).  The MPI-1 routine <tt>MPI_Errhandler_set</tt> may be used but
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its use is deprecated.  The predefined error handler
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<tt>MPI_ERRORS_RETURN</tt> may be used to cause error values to be returned.
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Note that MPI does not guarentee that an MPI program can continue past
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an error; however, MPI implementations will attempt to continue whenever
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possible.
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MPI_SUCCESS
No error; MPI routine completed successfully.
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MPI_ERR_TYPE
Invalid datatype argument. Additionally, this error can
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occur if an uncommitted MPI_Datatype (see <tt>MPI_Type_commit</tt>) is used
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in a communication call.
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MPI_ERR_COUNT
Invalid count argument. Count arguments must be
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non-negative; a count of zero is often valid.
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MPI_ERR_INTERN
This error is returned when some part of the MPICH
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implementation is unable to acquire memory.  
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MPI_ERR_ARG
Invalid argument. Some argument is invalid and is not
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identified by a specific error class (e.g., <tt>MPI_ERR_RANK</tt>).
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