This post talks about MPI_Comm_size function in MPI. MPI_Comm_size is a function in the Message Passing Interface (MPI) used to determine the total number of processes in a communicator. Syntax for MPI_Comm_size int MPI_Comm_size( MPI_Comm comm, int *size ) Input Parameters Output Parameter Example code – To compile this code, use following command – To…

This post talks about MPI_Init function in MPI. MPI_Init function is called at the beginning of an MPI program to set up the communication environment for all processes in the specified communicator. Without this function, none of the MPI operations will work. Syntax for MPI_Init int MPI_Init( int *argc, char ***argv ) Input Parameters Example…

This post talks about Reduction operation in MPI using MPI_Allreduce. MPI_Allreduce is a collective communication operation in the Message Passing Interface (MPI) that combines values from all processes in a communicator and distributes the result back to all processes. Syntax for MPI_Allreduce int MPI_Allreduce(const void *sendbuf, void *recvbuf, int count, MPI_Datatype datatype, MPI_Op op, MPI_Comm…

This post talks about MPI_Allgather function in MPI. MPI_Allgather is a collective communication operation in the Message Passing Interface (MPI) that allows all processes in a communicator to gather data from every other process. Unlike MPI_Gather, where only the root process collects the data, in MPI_Allgather, all processes receive the complete data from every other…

This post talks about Reduction operation in MPI using MPI_Gather. MPI_Gather is a collective operation in the Message Passing Interface (MPI) used to collect data from multiple processes and combine it into a single process. Syntax for MPI_Gather int MPI_Gather(const void *sendbuf, int sendcount, MPI_Datatype sendtype, void *recvbuf, int recvcount, MPI_Datatype recvtype, int root, MPI_Comm…