MPI_TYPE_HVECTOR(3)

🎀 NAME 🎀

hiii bestie, welcome to MPI_TYPE_HVECTOR(3), straight outta the Open MPI manual 💖

So boom: MPI_Type_hvector — and what it does is creates a vector (strided) datatype with offset in bytes ✨.

And now the sad part 😭: this routine is deprecated in favor of MPI_Type_create_hvector. It's giving "still works but please move on" energy. No cap.

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📜 SYNTAX 📜

💻 C Syntax

#include <mpi.h>

int MPI_Type_hvector(int count, int blocklength, MPI_Aint stride,
     MPI_Datatype oldtype, MPI_Datatype *newtype)

🧚 Fortran Syntax

USE MPI
! or the older form: INCLUDE 'mpif.h'

MPI_TYPE_HVECTOR(COUNT, BLOCKLENGTH, STRIDE, OLDTYPE, NEWTYPE,
             IERROR)
     INTEGER COUNT, BLOCKLENGTH, STRIDE, OLDTYPE
     INTEGER NEWTYPE, IERROR

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🫶 INPUT PARAMETERS 🫶

• count — how many blocks you want, bestie. A nonnegative integer, so don't come at it with a negative number 💅
• blocklength — how many elements live inside each block. Also a nonnegative integer 🌸
• stride — the number of bytes between the start of each block. It's an integer. Yes, bytes — that's the whole "h" thing in hvector, iykyk 🔥
• oldtype — the old datatype, aka the handle you're building on top of 🧱

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✨ OUTPUT PARAMETERS ✨

• newtype — the shiny new datatype handle you just manifested. Iconic 👑
• ierror — Fortran only: the error status (integer) 🫡

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💜 DESCRIPTION 💜

Okay so before we go any further, a lil vibe check: use of this routine is deprecated as of MPI-2 💀

Like, not "maybe don't", not "lowkey avoid" — deprecated. Periodt. Use MPI_Type_create_hvector instead 💖

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🚨 ERRORS 🚨

Almost all MPI routines return an error value; C routines as the return result of the function and Fortran routines in the last argument.

Before the error value is returned, the current MPI error handler associated with the communication object (e.g., communicator, window, file) is called. If no communication object is associated with the MPI call, then the call is considered attached to MPI_COMM_SELF and will call the associated MPI error handler. When MPI_COMM_SELF is not initialized (i.e., before MPI_Init/MPI_Init_thread, after MPI_Finalize, or when using the Sessions Model exclusively) the error raises the initial error handler. The initial error handler can be changed by calling MPI_Comm_set_errhandler on MPI_COMM_SELF when using the World model, or the mpi_initial_errhandler CLI argument to mpiexec or info key to MPI_Comm_spawn/MPI_Comm_spawn_multiple. If no other appropriate error handler has been set, then the MPI_ERRORS_RETURN error handler is called for MPI I/O functions and the MPI_ERRORS_ABORT error handler is called for all other MPI functions.

Open MPI includes three predefined error handlers that can be used:

• MPI_ERRORS_ARE_FATAL — causes the program to abort all connected MPI processes 😵
• MPI_ERRORS_ABORT — an error handler that can be invoked on a communicator, window, file, or session. When called on a communicator, it acts as if MPI_Abort was called on that communicator. If called on a window or file, acts as if MPI_Abort was called on a communicator containing the group of processes in the corresponding window or file. If called on a session, aborts only the local process 💅
• MPI_ERRORS_RETURN — returns an error code to the application 🫡

MPI applications can also implement their own error handlers by calling:

• MPI_Comm_create_errhandler then MPI_Comm_set_errhandler
• MPI_File_create_errhandler then MPI_File_set_errhandler
• MPI_Session_create_errhandler then MPI_Session_set_errhandler or at MPI_Session_init
• MPI_Win_create_errhandler then MPI_Win_set_errhandler

Note that MPI does not guarantee that an MPI program can continue past an error. Like, it might just keep going, it might not — no promises, babe 🙈

See the MPI man page for a full list of MPI error codes.

See the Error Handling section of the MPI-3.1 standard for more information.

See also:

• MPI_Type_create_hvector
• MPI_Type_vector

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🌈 Copyright 🌈

2003-2026, The Open MPI Community

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aaaand that's the whole page, bestie 🦋 thanks for reading all the way through, you're literally the main character ⭐ this was MPI_TYPE_HVECTOR(3) from the Open MPI crew, dated Sep 10, 2026 — go forth and use MPI_Type_create_hvector instead, mwah 💖💅