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In a model you have to call with OASIS3 :
In the namcouple it is possible to define less processors in the
coupling than the total number of processors (I/O server (NEMO) or I/O
In this case, by default, the ncpl first procs are the processors
implied in the coupling, it is not possible to choose.
processes not used in the coupling must only call prism_init and
library of IO : MPPIO
An appropriate use of the SEQ index can optimise a
coupled run when one of the component model is much slower than the
LOCTRANS transformations : no restart file.
The dimensions of the grids are optional in the namcouple.
With oasis3, the file areas.nc must be present to calculate to
statistics (checkin and/or checkout with int=1), else the program
you have to call with OASIS3-MCT :
All coupling is now direct. Gets are
blocking, puts are non-blocking.
MPI2 job launching is NOT supported.
Ability to send and receive more than 1 field with a coupling operation.
The dimensions of the grids must be given in the
Possibility to define less processors in the coupling than
the total number of processors (I/O server (NEMO) or I/O procs (WRF))
but chosing this time which
procs will be implied in the coupling. A communicator gathering only
these processes must be defined :
If such communicator does not exist yet in the code, the component
processes should use, to create it and give it to OASIS3-MCT :
couplcomm(icpl, local_comm, coupl_comm, kinfo) : icp = 1 for processes
participating in the coupling and with icpl=MPI_UNDEFINED for the
If this communicator already exist in the code, the component
should use, to provide it to OASIS3-MCT :
couplcomm(coupl_comm, kinfo) : coupl_com for processes
participating in the coupling and coupl_com=MPI_COMM_NULL
for the others.
processes not used in the coupling must call all collective
CALL oasis_def_partition ( with ig_paral=0 )
CALL oasis_def_var ( ... )
CALL oasis_enddef ( ... )
CALL oasis_terminate ( ... )
SEQ is not used anymore except if the implementation of
get/put ordering in models is important. But the SEQ setting in the
namcouple have to be consistent.
If restarts are used, both models call oasis_get before oasis_put and
SEQ must be equal to 1 for all coupling fields.
LOCTRANS transformation : restart file. If it is the only
transformation (ie no restart (LAG=0)) there is a particular fiel for
the variable. If there is a LAG (ie a restart) the variable is written
to the restart file.
With oasis3-mct, there is no abort even if the file areas.nc is not