mpi examples added

MPI/mpi-broadcast.c

@@ -0,0 +1,22 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include "mpi.h"
+
+int main(int argc, char *argv[])
+{
+ int rank, nprocs;
+ int param;
+
+ MPI_Init(&argc,&argv);
+ MPI_Comm_size(MPI_COMM_WORLD,&nprocs);
+ MPI_Comm_rank(MPI_COMM_WORLD,&rank);
+ srand(time(NULL)*rank);
+
+ if(rank==5) param = 23;
+
+ MPI_Bcast(&param,1,MPI_INT,5,MPI_COMM_WORLD);
+ printf("\nProcess %d received by broadcast value %d",rank,param);
+
+ MPI_Finalize();
+}

MPI/mpi-grouping-count.c

@@ -0,0 +1,43 @@
+#include <stdio.h>
+#include "mpi.h"
+
+int main(int argc, char *argv[])
+{
+ int rank, nprocs;
+ float vector[10];
+
+ MPI_Init(&argc,&argv);
+ MPI_Comm_size(MPI_COMM_WORLD,&nprocs);
+ MPI_Comm_rank(MPI_COMM_WORLD,&rank);
+
+ if (rank==0) {
+ /* Get the input values and write them in “vector”. */
+ /* As the values are the same type. */
+ int i=0;
+ for(i=0;i<10;i++) {
+ vector[i] = (float) i;
+ }
+
+ /*send the vector to the processes*/
+ for(i=1;i<nprocs;i++) {
+ MPI_Send((void*)vector, 10, MPI_FLOAT, i, 0, MPI_COMM_WORLD);
+ }
+
+ } else {
+ MPI_Status status;
+ /*recieve the data to work*/
+ MPI_Recv((void*)vector, 10, MPI_FLOAT, 0, MPI_ANY_TAG, MPI_COMM_WORLD, &status);
+ }
+
+ char result[500];
+ int i=0;
+
+ sprintf(result,"Process %d vector :",rank);
+
+ for(i=0;i<10;i++) {
+ sprintf(result,"%s %f",result,vector[i]);
+ }
+ printf("%s\n",result);
+
+ MPI_Finalize();
+}

MPI/mpi-grouping-pack.c

@@ -0,0 +1,50 @@
+#include <stdio.h>
+#include "mpi.h"
+
+int main(int argc, char *argv[])
+{
+ int rank, nprocs;
+
+ MPI_Init(&argc,&argv);
+ MPI_Comm_size(MPI_COMM_WORLD,&nprocs);
+ MPI_Comm_rank(MPI_COMM_WORLD,&rank);
+
+ char buffer[100]; // buffer to store the data(MPI_Pack/MPI_Unpack) 
+ int position; // the position of the buffer
+
+ float data1;
+ int data2;
+
+ if (rank== 0) {
+ //define the Data
+ data1=25.30;
+ data2=10;
+
+ //pack the data into buffer 
+ position=0; // Start at beginning of buffer 
+ MPI_Pack(&data1, 1, MPI_FLOAT, buffer, 100, &position, MPI_COMM_WORLD);
+ // Position has been incremented by sizeof(float) bytes 
+ MPI_Pack(&data2, 1, MPI_INT, buffer, 100, &position, MPI_COMM_WORLD);
+ // Send the contents of buffer to processors 
+ int i=0;
+ for(i=1; i<nprocs; i++) {
+ MPI_Send((void*)buffer, 100, MPI_PACKED, i,0, MPI_COMM_WORLD);
+ }
+ } else {
+ //Recieve the message
+ MPI_Status status;
+ MPI_Recv((void*)buffer,100,MPI_PACKED,0,MPI_ANY_TAG,MPI_COMM_WORLD,&status);
+ //Unpack the contents of buffer 
+ position=0;
+ MPI_Unpack(buffer, 100, &position, &data1, 1, MPI_FLOAT, MPI_COMM_WORLD);
+ MPI_Unpack(buffer, 100, &position, &data2, 1, MPI_INT, MPI_COMM_WORLD);
+
+ }
+
+ char result[500];
+ int i=0;
+ sprintf(result,"Process %d data %f %d",rank,data1,data2);
+ printf("%s\n",result);
+
+ MPI_Finalize();
+}

MPI/mpi-grouping-struct.c

@@ -0,0 +1,59 @@
+#include <stdio.h>
+#include "mpi.h"
+
+int main(int argc, char **argv )
+{
+ int rank,nprocs;
+ struct {float data1; int data2;char* data3;} data;
+ MPI_Datatype mydataStruct;
+ int blocks[3];
+ MPI_Aint indices[3];
+ MPI_Datatype MPItypes[3];
+
+ MPI_Init( &argc, &argv );
+ MPI_Comm_rank( MPI_COMM_WORLD, &rank );
+ MPI_Comm_size( MPI_COMM_WORLD, &nprocs);
+
+ /* One value of each type */
+ blocks[0] = 1;
+ blocks[1] = 1;
+ blocks[2] =10;
+ /* The base types */
+ MPItypes[0] = MPI_FLOAT;
+ MPItypes[1] = MPI_INT;
+ MPItypes[2] = MPI_CHAR;
+ /* The locations of each element */
+ MPI_Get_address( &data.data1, &indices[0] );
+ MPI_Get_address( &data.data2, &indices[1] );
+ MPI_Get_address( &data.data3, &indices[2] );
+ /* Make relative */
+ MPI_Aint baseaddres=indices[0];
+ indices[0] = indices[0] - baseaddres;
+ indices[1] = indices[1] - baseaddres;
+ indices[3] = indices[3] - baseaddres;
+ MPI_Type_create_struct( 3, blocks, indices, MPItypes, &mydataStruct );
+ MPI_Type_commit( &mydataStruct );
+
+
+ if (rank == 0) {
+ data.data1=25.30;
+ data.data2=7;
+ data.data3="String 10!";
+
+ int i;
+ for(i=1;i<nprocs;i++) {
+ MPI_Send(&data, 1, mydataStruct,i, 0, MPI_COMM_WORLD );
+ }
+ } else {
+ MPI_Status status;
+ MPI_Recv(&data,1,mydataStruct,0,MPI_ANY_TAG,MPI_COMM_WORLD,&status);
+ }
+
+ printf( "Process %d got %f, %d and %s\n", rank, data.data1, data.data2,data.data3 );
+
+ /* Clean up the type */
+ MPI_Type_free(&mydataStruct);
+ MPI_Finalize();
+
+ return 0;
+}

MPI/mpi-reduce-maxminloc.c

@@ -0,0 +1,34 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include "mpi.h"
+
+int main(int argc, char *argv[])
+{
+ int rank, nprocs, root;
+ struct {
+ double value;
+ int rank;
+ } in, out;
+
+ MPI_Init(&argc,&argv);
+ MPI_Comm_size(MPI_COMM_WORLD,&nprocs);
+ MPI_Comm_rank(MPI_COMM_WORLD,&rank);
+
+ root=0;
+
+ in.value=rank*10;
+ in.rank = rank;
+
+ MPI_Reduce(&in,&out,1,MPI_DOUBLE_INT,MPI_MAXLOC,root,MPI_COMM_WORLD);
+ if(rank==0) {
+ printf("Rank %d: max=%lf at rank = %d \n", rank,out.value,out.rank);
+ }
+
+ MPI_Reduce(&in,&out,1,MPI_DOUBLE_INT,MPI_MINLOC,root,MPI_COMM_WORLD);
+ if(rank==0) {
+ printf("Rank %d: min=%lf at rank = %d \n", rank,out.value,out.rank);
+ }
+
+ MPI_Finalize();
+}

MPI/mpi-reduce-onevalue.c

@@ -0,0 +1,28 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include "mpi.h"
+
+int main(int argc, char *argv[])
+{
+ int rank, nprocs;
+ int value;
+ int sumtotal;
+ int prodtotal;
+
+ MPI_Init(&argc,&argv);
+ MPI_Comm_size(MPI_COMM_WORLD,&nprocs);
+ MPI_Comm_rank(MPI_COMM_WORLD,&rank);
+
+ value = (rank+1)*10;
+
+ MPI_Reduce(&value,&sumtotal,1,MPI_INT,MPI_SUM,0,MPI_COMM_WORLD);
+ MPI_Reduce(&value,&prodtotal,1,MPI_INT,MPI_PROD,0,MPI_COMM_WORLD);
+
+ if(rank==0) {
+ printf("Collective sum result %d\n", sumtotal);
+ printf("Collective product results %d\n", prodtotal);
+ }
+
+ MPI_Finalize();
+}

MPI/mpi-reduce-vectors.c

@@ -0,0 +1,42 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include "mpi.h"
+
+int main(int argc, char *argv[])
+{
+ int rank, nprocs;
+ int vector[20];
+ int sum[20];
+ int i;
+ int result;
+
+ MPI_Init(&argc,&argv);
+ MPI_Comm_size(MPI_COMM_WORLD,&nprocs);
+ MPI_Comm_rank(MPI_COMM_WORLD,&rank);
+ srand(time(NULL)*rank);
+ //each processor initializes the vector
+ for(i=0;i<20;i++){
+ vector[i]=rand()%10;
+ }
+
+// printf("\nProcess %d vector: ",rank);
+// for(i=0;i<20;i++){
+// printf(" %d-%2d ",rank,vector[i]);
+// }
+// printf("\n\n");
+
+ //Apply MPI_SUM for each process and store result to sum
+ MPI_Reduce((void*)vector,&sum,20,MPI_INT,MPI_SUM,0,MPI_COMM_WORLD);
+
+ if(rank==0){
+ //process 0 obtains the results, calculates the final sum and prints
+ result=0;
+ for(i=0;i<20;i++) {
+ result+=sum[i];
+// printf(" %d ",sum[i]);
+ }
+ printf("sum = %d\n",result);
+ }
+ MPI_Finalize();
+}

MPI/mpi-status-struct.c

@@ -0,0 +1,27 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include "mpi.h"
+
+int main(int argc, char *argv[])
+{
+ int rank, nprocs, count, i;
+ float in[200],out[200];
+ MPI_Status status;
+
+ MPI_Init(&argc,&argv);
+ MPI_Comm_size(MPI_COMM_WORLD,&nprocs);
+ MPI_Comm_rank(MPI_COMM_WORLD,&rank);
+
+ if (rank==0) {
+ for (i=0; i<100; i++) out[i]=i;
+ MPI_Send(out,100,MPI_FLOAT,1,55,MPI_COMM_WORLD);
+ }
+ else {
+ MPI_Recv(in,200,MPI_FLOAT,MPI_ANY_SOURCE,55,MPI_COMM_WORLD,&status);
+ MPI_Get_count(&status,MPI_FLOAT,&count);
+ printf("Rank %d : Got %d data elements from processor %d.\n", rank, count, status.MPI_SOURCE);
+ }
+
+ MPI_Finalize();
+}