MPI CART CREATE With processes renamed in a 2d. No periodicity is imposed on the grid topology, we are able to second dimension( periods[1]=0) assign or distribute work,or Any reference to the column index distinguish among the processes by their grid topology rather than outside of its defined range(in this by their linear process ranks case 0 to 1)will result in a Additionally, we have imposed negative process rank(equal to periodicity along the first MPI PROC NULL Which is-1), dimension( periods[0]=1), which which signifies that it is out of means that any reference beyond range the first or last entry of any column Similarly, if periodicity was defined will be wrapped around cyclically only for the column index (i.e For example, row index i=-1, due periods[0]=0 periods[1]=1), each to periodicity, corresponds to i=2 row would wrap around itself Similarly. i=-2 maps onto i=1 Likewise,i=3 is the same asi=0MPI_CART_CREATE • With processes renamed in a 2D grid topology, we are able to assign or distribute work, or distinguish among the processes by their grid topology rather than by their linear process ranks. • Additionally, we have imposed periodicity along the first dimension ( periods[0]=1 ), which means that any reference beyond the first or last entry of any column will be wrapped around cyclically. • For example, row index i = -1, due to periodicity, corresponds to i = 2. Similarly, i = -2 maps onto i = 1. Likewise, i = 3 is the same as i = 0. • No periodicity is imposed on the second dimension ( periods[1]=0 ). Any reference to the column index outside of its defined range (in this case 0 to 1) will result in a negative process rank (equal to MPI_PROC_NULL which is -1), which signifies that it is out of range. • Similarly, if periodicity was defined only for the column index (i.e., periods[0]=0; periods[1]=1), each row would wrap around itself