.

Sheet7/Ex_5678/main.cpp

@@ -0,0 +1,67 @@
+#include <iostream>
+#include <mpi.h> 
+#include <vector>
+#include "VecFuncs.h"
+using namespace std;
+
+
+int main(int argc, char** argv)
+{
+    MPI_Init(&argc, &argv);
+    MPI_Comm icomm = MPI_COMM_WORLD;
+    int myrank;
+    MPI_Comm_rank(icomm, &myrank);
+
+    int n = 20;
+    vector<double> x(n);
+    vector<double> y = x;
+    for (int i = 0; i < n; ++i)
+    {
+        x[i] = myrank*100 + (i % 5)*10 + i;
+        y[i] = 1.0/(x[i]);
+    }
+    if(myrank == 0) // so scalar product is well defined (avoid division by 0)
+        y[0] = 0;
+    
+    //E5
+    if (myrank == 0) cout << "E5" << endl;
+    DebugVector(x, icomm);
+
+    //E6 
+    if (myrank == 0) cout << "E6" << endl;
+    double scalar_product = par_scalar(x, y, icomm);
+
+    if (myrank == 0)
+    {
+        cout << "<x,y> = " << scalar_product << endl << endl;
+    }
+
+    // E7
+	if (myrank == 0) cout << "E7" << endl;
+    double xmin, xmax;
+    par_minmax(x, xmin, xmax, icomm);
+
+	if (myrank == 0)
+    {
+        cout << "Global min: " << xmin << endl;
+        cout << "Global max: " << xmax << endl << endl;
+    }
+    
+    // E8
+    if (myrank == 0) cout << "E8" << endl;
+    vector<double> x_new(n);
+
+    // All to all
+    if (myrank == 0) cout << "All to all" << endl;
+    MPI_Alltoall(x.data(), 5, MPI_DOUBLE, x_new.data(), 5, MPI_DOUBLE, icomm);
+    DebugVector(x_new, icomm);
+    
+    if (myrank == 0) cout << "All to all (in place)" << endl;
+    MPI_Alltoall(MPI_IN_PLACE, 0, MPI_DOUBLE, x.data(), 5, MPI_DOUBLE, icomm);
+
+    DebugVector(x, icomm);
+
+
+    MPI_Finalize();
+    return 0;
+}