MPI_Op_commutative − Query of commutativity of reduction operation.
#include
<mpi.h>
int MPI_Op_commutative(MPI_Op op, int
*commute)
USE MPI
! or the older form: INCLUDE ’mpif.h’
MPI_OP_COMMUTATIVE(OP, COMMUTE, IERROR)
LOGICAL |
COMMUTE | |||
INTEGER |
OP, IERROR |
USE mpi_f08
MPI_Op_commutative(op, commute,
ierror)
TYPE(MPI_Op), INTENT(IN) :: op | |
INTEGER, INTENT(OUT) :: commute | |
INTEGER, OPTIONAL, INTENT(OUT) :: ierror |
op |
Operation (handle). |
commute |
True if op is commutative, false otherwise (logical). |
|||
IERROR |
Fortran only: Error status (integer). |
Reduction operations can be queried for their commutativity.
Almost all MPI routines return an error value; C routines as the value of the function and Fortran routines in the last argument. C++ functions do not return errors. If the default error handler is set to MPI::ERRORS_THROW_EXCEPTIONS, then on error the C++ exception mechanism will be used to throw an MPI::Exception object.
Before the error value is returned, the current MPI error handler is called. By default, this error handler aborts the MPI job, except for I/O function errors. The error handler may be changed with MPI_Comm_set_errhandler; the predefined error handler MPI_ERRORS_RETURN may be used to cause error values to be returned. Note that MPI does not guarantee that an MPI program can continue past an error.
MPI_Op_create