Changes between Version 32 and Version 33 of DRM4G/Tutorial

Timestamp:

Jun 27, 2016 9:26:27 AM (6 years ago)

Author:

carlos

Comment:

--

DRM4G/Tutorial

@@ -295 +295 @@
 {{{
 #!cpp
-  #include "mpi.h"
-  #include <stdio.h>
-  #include <math.h>
- 
-  int main( int argc, char *argv[])
-  {
-      int done = 0, n, myid, numprocs, i;
-      double PI25DT = 3.141592653589793238462643;
-      double mypi, pi, h, sum, x;
-      double startwtime = 0.0, endwtime;
-      int  namelen;
-      char processor_name[MPI_MAX_PROCESSOR_NAME];
- 
-      MPI_Init(&argc,&argv);
-      MPI_Comm_size(MPI_COMM_WORLD,&numprocs);
-      MPI_Comm_rank(MPI_COMM_WORLD,&myid);
-      MPI_Get_processor_name(processor_name,&namelen);
- 
-      printf("Process %d on %s\n", myid, processor_name);
- 
-      n = 100000000;
- 
-      startwtime = MPI_Wtime();
- 
-      h   = 1.0 / (double) n;
-      sum = 0.0;
-      for (i = myid + 1; i <= n; i += numprocs)
-      {
-          x = h * ((double)i - 0.5);
-          sum += 4.0 / (1.0 + x*x);
-      }
-      mypi = h * sum;
- 
-      MPI_Reduce(&mypi, &pi, 1, MPI_DOUBLE, MPI_SUM, 0, MPI_COMM_WORLD);
- 
-      if (myid == 0)
-      {
-          printf("pi is approximately %.16f, Error is %.16f\n",
-                 pi, fabs(pi - PI25DT));
-          endwtime = MPI_Wtime();
-          printf("wall clock time = %f\n", endwtime-startwtime);
-      }
- 
-      MPI_Finalize();
- 
-      return 0;
-  }
+#include "mpi.h"
+#include <stdio.h>
+#include <math.h>
+
+int main( int argc, char *argv[])
+{
+    int done = 0, n, myid, numprocs, i;
+    double PI25DT = 3.141592653589793238462643;
+    double mypi, pi, h, sum, x;
+    double startwtime = 0.0, endwtime;
+    int  namelen;
+    char processor_name[MPI_MAX_PROCESSOR_NAME];
+
+    MPI_Init(&argc,&argv);
+    MPI_Comm_size(MPI_COMM_WORLD,&numprocs);
+    MPI_Comm_rank(MPI_COMM_WORLD,&myid);
+    MPI_Get_processor_name(processor_name,&namelen);
+
+    printf("Process %d on %s\n", myid, processor_name);
+
+    n = 100000000;
+
+    startwtime = MPI_Wtime();
+
+    h   = 1.0 / (double) n;
+    sum = 0.0;
+    for (i = myid + 1; i <= n; i += numprocs)
+    {
+        x = h * ((double)i - 0.5);
+        sum += 4.0 / (1.0 + x*x);
+    }
+    mypi = h * sum;
+
+    MPI_Reduce(&mypi, &pi, 1, MPI_DOUBLE, MPI_SUM, 0, MPI_COMM_WORLD);
+
+    if (myid == 0)
+    {
+        printf("pi is approximately %.16f, Error is %.16f\n",
+               pi, fabs(pi - PI25DT));
+        endwtime = MPI_Wtime();
+        printf("wall clock time = %f\n", endwtime-startwtime);
+    }
+
+    MPI_Finalize();
+
+    return 0;
+}
 }}}