Folks, Does the standard specifiy the behavior of MPI_Dims_create() when the ndims argument is zero ? the standard only says negative input values of dims[i] are erroneous, but does not say anything about ndims. ndims is the number of Cartesian dimensions (integer), and though a negative number likely looks erroneous to most of us, a zero value is incorrect from a mathematical point of view (and i wish i remembered that ...) Could someone tell me how a zero value should be interpreted ? (e.g. valid/invalid/up to the implementor ?) FWIW, currently in MPICH, this is a no-op. In Open MPI, this is an error by default, but if parameter check is manually disabled, then this is a no-op too. Cheers, Gilles _______________________________________________ mpi-comments mailing list [email protected] https://lists.mpi-forum.org/mailman/listinfo/mpi-comments