MPIX_Nodecart_create
Create a Cartesian communicator, using information about which nodes are on the same process.
Synopsis
int MPIX_Nodecart_create(MPI_Comm comm_old, int ndims, const int dims[],
const int periods[], int reorder, MPI_Comm *comm_cart)
Input Parameters
- comm_old
- input communicator (handle)
- ndims
- number of dimensions of Cartesian grid (integer)
- dims
- integer array of size ndims specifying the number of processes in
each dimension
- periods
- logical array of size ndims specifying whether the grid is
periodic (true) or not (false) in each dimension
- reorder
- ranking may be reordered (true) or not (false) (logical)
Output Parameters
- comm_cart
- communicator with new Cartesian topology (handle)
Notes
Like MPI_Cart_create, the values for dims must be provided on input.
An option to consider is to allow zero values for elements of dims,
and then let this routine choose the dimensions to best fit the underlying
physical hardware.
The routine MPIX_Comm_dims_create may be used to determine good values
for dims.
The control variable cvar_nodecart_verbose may be set to a positive value
to cause output to be generated about this routine's operation.