examples/H5Part

- reviewed

examples/H5Part/write_setnparticles.c

@@ -7,44 +7,46 @@
   License: see file COPYING in top level of source distribution.
 */
 
-#include <stdlib.h>
 #include "H5hut.h"
 
-#define DEFAULT_VERBOSITY       H5_VERBOSE_DEFAULT
+// name of output file
+const char* fname = "example_setnparticles.h5";
 
-#define FNAME                   "example_setnparticles.h5"
-#define NUM_PARTICLES           3
+// H5hut verbosity level
+const h5_int64_t h5_verbosity = H5_VERBOSE_DEFAULT;
+
+// number of particles we are going to write per core
+const h5_int64_t num_particles = 99;
 
 int
 main (
         int argc,
         char* argv[]
         ){
-        h5_int64_t verbosity = DEFAULT_VERBOSITY;
 
         // initialize MPI & H5hut
         MPI_Init (&argc, &argv);
         MPI_Comm comm = MPI_COMM_WORLD;
-        int rank = 0;
-        MPI_Comm_rank (comm, &rank);
-
+        int comm_size = 1;
+        MPI_Comm_size (comm, &comm_size);
+        int comm_rank = 0;
+        MPI_Comm_rank (comm, &comm_rank);
         H5AbortOnError ();
-        H5SetVerbosityLevel (verbosity);
+        H5SetVerbosityLevel (h5_verbosity);
 
-        // create fake data
-        h5_int32_t data[NUM_PARTICLES];
-        h5_int64_t num_particles = NUM_PARTICLES;
-        for (int i = 0; i < num_particles; i++) {
-                data[i] = i + num_particles * rank;
-        }
-
-        // open file and create step #0
-        h5_file_t file = H5OpenFile (FNAME, H5_O_WRONLY, H5_PROP_DEFAULT);
+        // open file and create first step
+        h5_file_t file = H5OpenFile (fname, H5_O_WRONLY, H5_PROP_DEFAULT);
         H5SetStep (file, 0); 
 
-        // define number of items this process will write
+        // define number of particles this process will write
         H5PartSetNumParticles (file, num_particles);
 
+	// create fake data
+        h5_int32_t data[num_particles];
+        for (int i = 0; i < num_particles; i++) {
+                data[i] = i + num_particles * comm_rank;
+        }
+
         // write data
         H5PartWriteDataInt32 (file, "data", data);