It depends on how you define min array. Do you want to get the minimum value at each index? The full array with the minimum sum? Something else? On Feb 15, 2014, at 6:22 AM, 维洛逐风 <[email protected]<mailto:[email protected]>> wrote: HI. Say,I have 10 process，each one has a array called gbest, I want to get the min array(with a compare operation I want to define). Is there a way to use MPI_REDUCE to do this?As I know, MPI_MIN specifies datatypes(without arrays). ------------------ Jie-Jun Wu Department of Computer Science, Sun Yat-sen University, Guangzhou, P.R. China _______________________________________________ discuss mailing list [email protected]<mailto:[email protected]> To manage subscription options or unsubscribe: https://lists.mpich.org/mailman/listinfo/discuss