C++ H5Dopen函数代码示例

int main (int argc, char* argv[])
{
   // Library initilization.
   MPI_Init(&argc, &argv);
   herr_t H5open();
   std::string filename = argv[1];

   // We determine the size and ranks of our process.
   int rank, size;
   MPI_Comm_rank(MPI_COMM_WORLD, &rank);
   MPI_Comm_size(MPI_COMM_WORLD, &size);

   // We distribute the indices among the processors. 
   // For proper load balancing, we should have size % 6 = 0. 
   std::vector<std::vector<unsigned int> > indices;
   indices.resize(size);

   for (unsigned int i=0; i<6; i++)
   {
    int idx = user_mod(i,size);
    indices[idx].push_back(i);
   }

   // Open existing file.
   hid_t plist_id;
   plist_id = H5Pcreate(H5P_FILE_ACCESS);
   H5Pset_fapl_mpio(plist_id,MPI_COMM_WORLD,MPI_INFO_NULL); 
   hid_t file_id = H5Fopen(filename.c_str(), H5F_ACC_RDONLY, plist_id);

   // We store the name of the datasets we want to open. 
   std::vector<std::string> dataset_names;
   dataset_names.push_back(std::string("/besselJ"));
   dataset_names.push_back(std::string("/besselY"));
   dataset_names.push_back(std::string("/besselI"));
   dataset_names.push_back(std::string("/besselK"));
   dataset_names.push_back(std::string("/hankelH1"));
   dataset_names.push_back(std::string("/hankelH2"));

   // We store the appropriate functions pointers in an array.
   std::vector<std::complex<double> (*) (double, std::complex<double>, int)> f_ptr;
   f_ptr.push_back(sp_bessel::besselJp);
   f_ptr.push_back(sp_bessel::besselYp);
   f_ptr.push_back(sp_bessel::besselIp);
   f_ptr.push_back(sp_bessel::besselKp);
   f_ptr.push_back(sp_bessel::hankelH1p);
   f_ptr.push_back(sp_bessel::hankelH2p);

   // We loop over the datasets.
   for (auto iter = indices[rank].begin(); iter != indices[rank].end(); iter++)
   {
    // Open dataset.
    hid_t dataset_id = H5Dopen(file_id, dataset_names[*iter].c_str(), H5P_DEFAULT);

    // Obtain the dataspace
    hid_t dspace = H5Dget_space(dataset_id);

    // We obtain the dimensions of the dataset.
    const int ndims = H5Sget_simple_extent_ndims(dspace);
    hsize_t dims[ndims];
    H5Sget_simple_extent_dims(dspace, dims, NULL);

    // We read the dataset.
    std::complex<double> values[dims[0]][dims[1]][dims[2]][dims[3]];
    hid_t complex_id = H5Dget_type(dataset_id);
    H5Dread(dataset_id, complex_id, H5S_ALL, H5S_ALL, H5P_DEFAULT, values);

    // We now open/read the attributes.
    double vmax, zimin, zimax, zrmin, zrmax;
    hid_t vmax_id = H5Aopen(dataset_id, "vmax", H5P_DEFAULT);
    hid_t zimin_id = H5Aopen(dataset_id, "zimin", H5P_DEFAULT);
    hid_t zimax_id = H5Aopen(dataset_id, "zrmax", H5P_DEFAULT);
    hid_t zrmin_id = H5Aopen(dataset_id, "zrmin", H5P_DEFAULT);
    hid_t zrmax_id = H5Aopen(dataset_id, "zrmax", H5P_DEFAULT);

    H5Aread(vmax_id, H5T_NATIVE_DOUBLE, &vmax);
    H5Aread(zimin_id, H5T_NATIVE_DOUBLE, &zimin);
    H5Aread(zimax_id, H5T_NATIVE_DOUBLE, &zimax);
    H5Aread(zrmin_id, H5T_NATIVE_DOUBLE, &zrmin);
    H5Aread(zrmax_id, H5T_NATIVE_DOUBLE, &zrmax);

    // We now evaluate the Bessel functions at the computed values.
    arma::vec orders = arma::linspace(-vmax, vmax, dims[1]);
    arma::vec realZ = arma::linspace(zrmin, zrmax, dims[2]);
    arma::vec imagZ = arma::linspace(zimin, zimax, dims[3]);


    unsigned int count = 0;
    for (int i=0; i<dims[0]; i++)
    {
        for (int j=0; j<dims[1]; j++)
        {
            for (int k=0; k<dims[2]; k++)
            {
                for (int l=0; l<dims[3]; l++)
                {
                    double eps = std::abs(f_ptr[*iter](orders(j), std::complex<double>(realZ(k), imagZ(l)), i)
                                            - values[i][j][k][l]);

                    if (eps > 1.0e-13)
                    {
//.........这里部分代码省略.........

int
main (void)
{
    hid_t       file, filetype, memtype, space, dset;
                                    /* Handles */
    herr_t      status;
    hvl_t       wdata[2],           /* Array of vlen structures */
                *rdata;             /* Pointer to vlen structures */
    hsize_t     dims[1] = {2};
    int         *ptr,
                ndims,
                i, j;

    /*
     * Initialize variable-length data.  wdata[0] is a countdown of
     * length LEN0, wdata[1] is a Fibonacci sequence of length LEN1.
     */
    wdata[0].len = LEN0;
    ptr = (int *) malloc (wdata[0].len * sizeof (int));
    for (i=0; i<wdata[0].len; i++)
        ptr[i] = wdata[0].len - (size_t)i;       /* 3 2 1 */
    wdata[0].p = (void *) ptr;

    wdata[1].len = LEN1;
    ptr = (int *) malloc (wdata[1].len * sizeof (int));
    ptr[0] = 1;
    ptr[1] = 1;
    for (i=2; i<wdata[1].len; i++)
        ptr[i] = ptr[i-1] + ptr[i-2];   /* 1 1 2 3 5 8 etc. */
    wdata[1].p = (void *) ptr;

    /*
     * Create a new file using the default properties.
     */
    file = H5Fcreate (FILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);

    /*
     * Create variable-length datatype for file and memory.
     */
    filetype = H5Tvlen_create (H5T_STD_I32LE);
    memtype = H5Tvlen_create (H5T_NATIVE_INT);

    /*
     * Create dataspace.  Setting maximum size to NULL sets the maximum
     * size to be the current size.
     */
    space = H5Screate_simple (1, dims, NULL);

    /*
     * Create the dataset and write the variable-length data to it.
     */
    dset = H5Dcreate (file, DATASET, filetype, space, H5P_DEFAULT, H5P_DEFAULT,
                H5P_DEFAULT);
    status = H5Dwrite (dset, memtype, H5S_ALL, H5S_ALL, H5P_DEFAULT, wdata);

    /*
     * Close and release resources.  Note the use of H5Dvlen_reclaim
     * removes the need to manually free() the previously malloc'ed
     * data.
     */
    status = H5Dvlen_reclaim (memtype, space, H5P_DEFAULT, wdata);
    status = H5Dclose (dset);
    status = H5Sclose (space);
    status = H5Tclose (filetype);
    status = H5Tclose (memtype);
    status = H5Fclose (file);


    /*
     * Now we begin the read section of this example.  Here we assume
     * the dataset has the same name and rank, but can have any size.
     * Therefore we must allocate a new array to read in data using
     * malloc().
     */

    /*
     * Open file and dataset.
     */
    file = H5Fopen (FILE, H5F_ACC_RDONLY, H5P_DEFAULT);
    dset = H5Dopen (file, DATASET, H5P_DEFAULT);

    /*
     * Get dataspace and allocate memory for array of vlen structures.
     * This does not actually allocate memory for the vlen data, that
     * will be done by the library.
     */
    space = H5Dget_space (dset);
    ndims = H5Sget_simple_extent_dims (space, dims, NULL);
    rdata = (hvl_t *) malloc (dims[0] * sizeof (hvl_t));

    /*
     * Create the memory datatype.
     */
    memtype = H5Tvlen_create (H5T_NATIVE_INT);

    /*
     * Read the data.
     */
    status = H5Dread (dset, memtype, H5S_ALL, H5S_ALL, H5P_DEFAULT, rdata);

//.........这里部分代码省略.........

void BAGDataset::LoadMetadata()

{
/* -------------------------------------------------------------------- */
/*      Load the metadata from the file.                                */
/* -------------------------------------------------------------------- */
    hid_t hMDDS = H5Dopen( hHDF5, "/BAG_root/metadata" );
    hid_t datatype     = H5Dget_type( hMDDS );
    hid_t dataspace    = H5Dget_space( hMDDS );
    hid_t native       = H5Tget_native_type( datatype, H5T_DIR_ASCEND );
    hsize_t dims[3], maxdims[3];

    H5Sget_simple_extent_dims( dataspace, dims, maxdims );

    pszXMLMetadata = (char *) CPLCalloc(dims[0]+1,1);

    H5Dread( hMDDS, native, H5S_ALL, dataspace, H5P_DEFAULT, pszXMLMetadata );

    H5Sclose( dataspace );
    H5Tclose( datatype );
    H5Dclose( hMDDS );

    if( strlen(pszXMLMetadata) == 0 )
        return;

/* -------------------------------------------------------------------- */
/*      Try to get the geotransform.                                    */
/* -------------------------------------------------------------------- */
    CPLXMLNode *psRoot = CPLParseXMLString( pszXMLMetadata );

    if( psRoot == NULL )
        return;

    CPLStripXMLNamespace( psRoot, NULL, TRUE );

    CPLXMLNode *psGeo = CPLSearchXMLNode( psRoot, "=MD_Georectified" );

    if( psGeo != NULL )
    {
        char **papszCornerTokens = 
            CSLTokenizeStringComplex( 
                CPLGetXMLValue( psGeo, "cornerPoints.Point.coordinates", "" ),
                " ,", FALSE, FALSE );

        if( CSLCount(papszCornerTokens ) == 4 )
        {
            double dfLLX = atof( papszCornerTokens[0] );
            double dfLLY = atof( papszCornerTokens[1] );
            double dfURX = atof( papszCornerTokens[2] );
            double dfURY = atof( papszCornerTokens[3] );

            adfGeoTransform[0] = dfLLX;
            adfGeoTransform[1] = (dfURX - dfLLX) / (GetRasterXSize()-1);
            adfGeoTransform[3] = dfURY;
            adfGeoTransform[5] = (dfLLY - dfURY) / (GetRasterYSize()-1);

            adfGeoTransform[0] -= adfGeoTransform[1] * 0.5;
            adfGeoTransform[3] -= adfGeoTransform[5] * 0.5;
        }
        CSLDestroy( papszCornerTokens );
    }

    CPLDestroyXMLNode( psRoot );

/* -------------------------------------------------------------------- */
/*      Try to get the coordinate system.                               */
/* -------------------------------------------------------------------- */
    OGRSpatialReference oSRS;

    if( OGR_SRS_ImportFromISO19115( &oSRS, pszXMLMetadata )
        == OGRERR_NONE )
    {
        oSRS.exportToWkt( &pszProjection );
    }
}

int main (int argc, char ** argv) 
{
    char        filename [256];
    int         rank, size, i, j;
    MPI_Comm    comm = MPI_COMM_WORLD;
    uint64_t start[2], count[2], bytes_read = 0;
    int ndims, nsf;
    hid_t file;
    hid_t dataset;
    hid_t filespace;
    hid_t memspace;

    MPI_Init (&argc, &argv);
    MPI_Comm_rank (comm, &rank);
    MPI_Comm_size (comm, &size);

    int data_out[size];

    MPI_Barrier (comm);
    struct timeval t1;
    gettimeofday (&t1, NULL);

    strcpy (filename, "pixie3d.bp");
    {
        file = H5Fopen(filename, H5F_ACC_RDONLY, H5P_DEFAULT);
        dataset = H5Dopen(file, "index");
        filespace = H5Dget_space(dataset);    /* Get filespace handle first. */
        ndims     = H5Sget_simple_extent_ndims(filespace);

        hsize_t dims[ndims];
        herr_t status_n  = H5Sget_simple_extent_dims(filespace, dims, NULL);
/*
        printf("dataset rank %d, dimensions %lu\n",
	       ndims, (unsigned long)(dims[0]));
*/
       if (dims[0] != size)
       {
           printf ("can only support same # of reader as writers\n");
           exit (0);
       }
       /*
        * Define the memory space to read dataset.
        */
        memspace = H5Screate_simple(ndims,dims,NULL);

        /*
         * Read dataset back and display.
         */
        herr_t status = H5Dread(dataset, H5T_NATIVE_INT, memspace, filespace,
	          	     H5P_DEFAULT, data_out);
    }

    int temp_index[size];
    int temp;
    memcpy (temp_index, data_out, 4 * size);
  
    nsf = 0;
    for (i = 0; i < size - 1; i++)
    {
        if (temp_index[i] > temp_index[i + 1])
        {
            temp = temp_index[i];
            temp_index[i] = temp_index[i + 1];
            temp_index[i + 1] = temp;
        }
    }

    nsf = temp_index[size - 1] + 1;

    int group_size = size / nsf;
    int grpid = rank / group_size;
    int token;
    MPI_Status status;
    MPI_Comm new_comm;
    MPI_Comm_split (comm, grpid, rank, &new_comm);
    int new_rank;
    MPI_Comm_rank (new_comm, &new_rank);


    if (new_rank == 0)
    {
        // data is in f_idx subfile.
        int f_idx = data_out[rank];
        char temp_string[100], * fname;
        strcpy (temp_string, filename);
        fname = strtok (temp_string, ".");

        sprintf (temp_string
                ,"%s_%d.bp"
                ,fname
                ,f_idx
                );
        file = H5Fopen(temp_string, H5F_ACC_RDONLY, H5P_DEFAULT);
        sprintf (temp_string, "Var7_%d", rank);
        dataset = H5Dopen(file, temp_string);
        filespace = H5Dget_space(dataset);    /* Get filespace handle first. */
        ndims     = H5Sget_simple_extent_ndims(filespace);

        hsize_t dims[ndims];
        herr_t status_n  = H5Sget_simple_extent_dims(filespace, dims, NULL);
//.........这里部分代码省略.........

PyObject *H5UIget_info( hid_t loc_id,
                        const char *dset_name,
                        char *byteorder)
{
  hid_t       dataset_id;
  int         rank;
  hsize_t     *dims;
  hid_t       space_id;
  H5T_class_t class_id;
  H5T_order_t order;
  hid_t       type_id;
  PyObject    *t;
  int         i;

  /* Open the dataset. */
  if ( (dataset_id = H5Dopen( loc_id, dset_name, H5P_DEFAULT )) < 0 ) {
    Py_INCREF(Py_None);
    return Py_None;     /* Not chunked, so return None */
  }

  /* Get an identifier for the datatype. */
  type_id = H5Dget_type( dataset_id );

  /* Get the class. */
  class_id = H5Tget_class( type_id );

  /* Get the dataspace handle */
  if ( (space_id = H5Dget_space( dataset_id )) < 0 )
    goto out;

  /* Get rank */
  if ( (rank = H5Sget_simple_extent_ndims( space_id )) < 0 )
    goto out;

  /* Book resources for dims */
  dims = (hsize_t *)malloc(rank * sizeof(hsize_t));

  /* Get dimensions */
  if ( H5Sget_simple_extent_dims( space_id, dims, NULL) < 0 )
    goto out;

  /* Assign the dimensions to a tuple */
  t = PyTuple_New(rank);
  for(i=0;i<rank;i++) {
    /* I don't know if I should increase the reference count for dims[i]! */
    PyTuple_SetItem(t, i, PyInt_FromLong((long)dims[i]));
  }

  /* Release resources */
  free(dims);

  /* Terminate access to the dataspace */
  if ( H5Sclose( space_id ) < 0 )
    goto out;

  /* Get the byteorder */
  /* Only integer, float, time and enum classes can be byteordered */
  if ((class_id == H5T_INTEGER) || (class_id == H5T_FLOAT)
      || (class_id == H5T_BITFIELD) || (class_id == H5T_TIME)
      ||  (class_id == H5T_ENUM)) {
    order = H5Tget_order( type_id );
    if (order == H5T_ORDER_LE)
      strcpy(byteorder, "little");
    else if (order == H5T_ORDER_BE)
      strcpy(byteorder, "big");
    else {
      fprintf(stderr, "Error: unsupported byteorder: %d\n", order);
      goto out;
    }
  }
  else {
    strcpy(byteorder, "irrelevant");
  }

  /* End access to the dataset */
  H5Dclose( dataset_id );

  /* Return the dimensions tuple */
  return t;

out:
 H5Tclose( type_id );
 H5Dclose( dataset_id );
 Py_INCREF(Py_None);
 return Py_None;    /* Not chunked, so return None */

}

int main(int argc, char* argv[])
{
    char c;
    int ix, iy, iz, i;
    MPI_Comm mpicomm;
    MPI_Info mpiinfo;
    int mpirank;
    int mpisize;
    double *data3d, *data2d, *x, *y, *z, t;
    int localx, localy, localwidth, localheight;
    int maxwidth, maxheight;
    const char* filename = "output.h5";
    hid_t fileid, plist, filespace, memspace, dimvar, varid;
    hsize_t size[NDIMS], maxsize[NDIMS], chunksize[NDIMS];
    hsize_t start[NDIMS], count[NDIMS];
    char varname[32];

    mpicomm = MPI_COMM_WORLD;
    mpiinfo = MPI_INFO_NULL;

    MPI_Init(&argc, &argv);
    MPI_Comm_size(mpicomm, &mpisize);
    MPI_Comm_rank(mpicomm, &mpirank);

    if(! mpirank) printf("Creating some data...\n");

    // Distribute our data values in a pism-y way
    GetLocalBounds(XSIZE, YSIZE, mpirank, mpisize,
                   &localx, &localy, &localwidth, &localheight);
    printf("Rank%02d: x=%d, y=%d, width=%d, height=%d\n",
           mpirank, localx, localy, localwidth, localheight);

    data2d = (double*)malloc(localwidth * localheight * sizeof(double));
    data3d = (double*)malloc(localwidth * localheight * ZSIZE * sizeof(double));
    x = (double*)malloc(localwidth * sizeof(double));
    y = (double*)malloc(localheight * sizeof(double));
    z = (double*)malloc(ZSIZE * sizeof(double));
    t = 0.0;
    for(ix = 0; ix < localwidth; ix++)
    {
        x[ix] = ix + localx;
        for(iy = 0; iy < localheight; iy++)
        {
            y[iy] = iy + localy;
            data2d[ix*localheight + iy] = (ix+localx)*localheight + iy+localy;
            for(iz = 0; iz < ZSIZE; iz++)
            {
                z[iz] = iz;
                data3d[ix*localheight*ZSIZE + iy*ZSIZE + iz] =
                    (ix+localx)*YSIZE*ZSIZE + (iy+localy)*ZSIZE + iz;
            }
        }
    }

    if(! mpirank) printf("Creating HDF5 file...\n");

    plist = H5Pcreate(H5P_FILE_ACCESS);
    H5Pset_fapl_mpio(plist, mpicomm, mpiinfo);

    // TODO: this seems like a good place to put optimizations, and indeed
    // PISM is adding several additional properties, like setting block sizes,
    // cache eviction policies, fs striping parameters, etc.

    fileid = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, plist);
    H5Pclose(plist);

    if(! mpirank) printf("Setting up dimensions...\n");

    if(! mpirank) printf("Creating time dimension...\n");

    // Define the time dimension
    size[0] = 1;
    maxsize[0] = H5S_UNLIMITED;
    chunksize[0] = 1;

    filespace = H5Screate_simple(1, size, maxsize);
    plist = H5Pcreate(H5P_DATASET_CREATE);
    H5Pset_chunk(plist, 1, chunksize);  // It is strictly required to set chunksize when using
    // the low-level api.  Contiguous datasets are not allowed
    // to use the unlimited dimension.
    dimvar = H5Dcreate(fileid, TNAME, H5T_NATIVE_DOUBLE, filespace,
                       H5P_DEFAULT, plist, H5P_DEFAULT);
    H5Pclose(plist);
    H5DSset_scale(dimvar, TNAME);
    H5Dclose(dimvar);
    H5Sclose(filespace);

#ifdef OLD_WRITE_PATTERN
    if(! mpirank) printf("Writing time dimension...\n");
    dimvar = H5Dopen(fileid, TNAME, H5P_DEFAULT);
    filespace = H5Dget_space(dimvar);
    memspace = H5Screate_simple(1, size, 0);
    plist = H5Pcreate(H5P_DATASET_XFER);
    H5Pset_dxpl_mpio(plist, H5FD_MPIO_COLLECTIVE); // TODO: Pism does this, but comments suggest it is questionable
    start[0] = 0;
    count[0] = 1;
    H5Sselect_hyperslab(filespace, H5S_SELECT_SET, start, 0, count, 0);
    H5Dwrite(dimvar, H5T_NATIVE_DOUBLE, memspace, filespace, plist, &t);
    H5Pclose(plist);
    H5Sclose(filespace);
//.........这里部分代码省略.........

//.........这里部分代码省略.........
#ifdef USE_MPE
	 MPE_Log_event(e_write, 0, "end write file");
#endif /* USE_MPE */
      }
      write_us = (MPI_Wtime() - ftime) * MILLION;
      MPI_Reduce(&write_us, &max_write_us, 1, MPI_INT, MPI_MAX, 0, MPI_COMM_WORLD);
      if (!my_rank)
      {
	 write_rate = (float)(DIM2_LEN * sizeof(int))/(float)max_write_us;      
	 printf("\np=%d, write_rate=%g", p, write_rate);
      }
      
#ifdef USE_MPE
      MPE_Log_event(s_close, 0, "start close file");
#endif /* USE_MPE */

      /* Close. These collective operations will allow every process
       * to catch up. */
      if (H5Dclose(dsid) < 0 ||
      H5Sclose(whole_spaceid) < 0 ||
      H5Sclose(slice_spaceid) < 0 ||
      H5Pclose(fapl_id) < 0 ||
      H5Fclose(fileid) < 0)
	 ERR;

#ifdef USE_MPE
      MPE_Log_event(e_close, 0, "end close file");
#endif /* USE_MPE */

      /* Open the file. */
      if ((fapl_id = H5Pcreate(H5P_FILE_ACCESS)) < 0) ERR;
      if (H5Pset_fapl_mpio(fapl_id, MPI_COMM_WORLD, MPI_INFO_NULL) < 0) ERR;


      if (H5Pset_libver_bounds(fapl_id, H5F_LIBVER_LATEST, H5F_LIBVER_LATEST) < 0) ERR;
      if ((fileid = H5Fopen(FILE_NAME, H5F_ACC_RDONLY, fapl_id)) < 0) ERR;

      /* Create a space to deal with one slice in memory. */
      dims[0] = SC1;
      if ((slice_spaceid = H5Screate_simple(NDIMS, dims, NULL)) < 0) ERR;

      /* Open the dataset. */
      if ((dsid = H5Dopen(fileid, VAR_NAME)) < 0) ERR;
      if ((whole_spaceid1 = H5Dget_space(dsid)) < 0) ERR;

      ftime = MPI_Wtime();      
      
      /* Read the data, a slice at a time. */
      for (s = 0; s < num_steps; s++)
      {
	 /* Select hyperslab for read of one slice. */
	 start[0] = s * SC1 * p + my_rank * SC1;
	 count[0] = SC1;
	 if (H5Sselect_hyperslab(whole_spaceid1, H5S_SELECT_SET, 
	 start, NULL, count, NULL) < 0) 
	 {
	    ERR;
	    return 2;
	 }

	 if (H5Dread(dsid, H5T_NATIVE_INT, slice_spaceid, whole_spaceid1, 
	 H5P_DEFAULT, data_in) < 0) 
	 {
	    ERR;
	    return 2;
	 }

/* 	 /\* Check the slice of data. *\/ */
/* 	 for (i = 0; i < SC1; i++) */
/* 	    if (data[i] != data_in[i])  */
/* 	    { */
/* 	       ERR; */
/* 	       return 2; */
/* 	    } */
      }
      read_us = (MPI_Wtime() - ftime) * MILLION;
      MPI_Reduce(&read_us, &max_read_us, 1, MPI_INT, MPI_MAX, 0, MPI_COMM_WORLD);
      if (!my_rank)
      {
	 read_rate = (float)(DIM2_LEN * sizeof(int))/(float)max_read_us;      
	 printf(", read_rate=%g\n", read_rate);
      }
      
      /* Close down. */
      if (H5Dclose(dsid) < 0 ||
      H5Sclose(slice_spaceid) < 0 ||
      H5Sclose(whole_spaceid1) < 0 ||
      H5Pclose(fapl_id) < 0 ||
      H5Fclose(fileid) < 0)
	 ERR;
   }
   if (!my_rank)
      SUMMARIZE_ERR;

   MPI_Finalize();

   if (!my_rank)
      FINAL_RESULTS;
   return 0;
}

int _io_write(cow_dfield *f, char *fname)
// -----------------------------------------------------------------------------
// This function uses a collective MPI-IO procedure to write the contents of
// 'data' to the HDF5 file named 'fname', which is assumed to have been created
// already. The dataset with name 'dname', which is being written to, must not
// exist already. Chunking is enabled as per the ChunkSize variable, and is
// disabled by default. Recommended chunk size is local subdomain size. This
// will result in optimized read/write on the same decomposition layout, but
// poor performance for different access patterns, for example the slabs used by
// cluster-FFT functions.
//
//                                   WARNING!
//
// All processors must define the same chunk size, the behavior of this function
// is not defined otherwise. This implies that chunking should be disabled when
// running on a strange number of cores, and subdomain sizes are non-uniform.
// -----------------------------------------------------------------------------
{
  cow_domain *d = f->domain;
  char **pnames = f->members;
  void *data = f->data;
  char *gname = f->name;
  int n_memb = f->n_members;
  int n_dims = d->n_dims;
  hsize_t *L_nint = d->L_nint_h5;
  hsize_t *G_strt = d->G_strt_h5;
  hsize_t *G_ntot = d->G_ntot_h5;

  hsize_t ndp1 = n_dims + 1;
  hsize_t l_nint[4];
  hsize_t l_ntot[4];
  hsize_t l_strt[4];
  hsize_t stride[4];

  for (int i=0; i<n_dims; ++i) {
    l_nint[i] = d->L_nint[i]; // Selection size, target and destination
    l_ntot[i] = d->L_ntot[i]; // Memory space total size
    l_strt[i] = d->L_strt[i]; // Memory space selection start
    stride[i] = 1;
  }
  l_nint[ndp1 - 1] = 1;
  l_ntot[ndp1 - 1] = n_memb;
  stride[ndp1 - 1] = n_memb;

  // The loop over processors is needed if COW_MPI support is enabled and
  // COW_HDF5_MPI is not. If either COW_MPI is disabled, or COW_HDF5_MPI is
  // enabled, then the write calls occur without the loop.
  // ---------------------------------------------------------------------------
  int sequential = 0;
  int rank = 0;
#if (!COW_HDF5_MPI && COW_MPI)
  sequential = 1;
  for (rank=0; rank<d->cart_size; ++rank) {
    if (rank == d->cart_rank) {
#endif
      hid_t file = H5Fopen(fname, H5F_ACC_RDWR, d->fapl);
      hid_t memb = H5Gopen(file, gname, H5P_DEFAULT);
      hid_t mspc = H5Screate_simple(ndp1, l_ntot, NULL);
      hid_t fspc = H5Screate_simple(n_dims, G_ntot, NULL);
      hid_t dset;
      for (int n=0; n<n_memb; ++n) {
	if (sequential && rank != 0) {
	  dset = H5Dopen(memb, pnames[n], H5P_DEFAULT);
	}
	else {
	  dset = H5Dcreate(memb, pnames[n], H5T_NATIVE_DOUBLE, fspc,
			   H5P_DEFAULT, d->dcpl, H5P_DEFAULT);
	}
	l_strt[ndp1 - 1] = n;
	H5Sselect_hyperslab(mspc, H5S_SELECT_SET, l_strt, stride, l_nint, NULL);
	H5Sselect_hyperslab(fspc, H5S_SELECT_SET, G_strt, NULL, L_nint, NULL);
	H5Dwrite(dset, H5T_NATIVE_DOUBLE, mspc, fspc, d->dxpl, data);
	H5Dclose(dset);
      }
      H5Sclose(fspc);
      H5Sclose(mspc);
      H5Gclose(memb);
      H5Fclose(file);
#if (!COW_HDF5_MPI && COW_MPI)
    }
    if (cow_mpirunning()) {
      MPI_Barrier(d->mpi_cart);
    }
  }
#endif // !COW_HDF5_MPI && COW_MPI
  return 0;
}

int _io_read(cow_dfield *f, char *fname)
{
  cow_domain *d = f->domain;
  char **pnames = f->members;
  void *data = f->data;
  char *gname = f->name;
  int n_memb = f->n_members;
  int n_dims = d->n_dims;
  hsize_t *L_nint = d->L_nint_h5;
  hsize_t *G_strt = d->G_strt_h5;
  hsize_t *G_ntot = d->G_ntot_h5;

  hsize_t ndp1 = n_dims + 1;
  hsize_t l_nint[4];
  hsize_t l_ntot[4];
  hsize_t l_strt[4];
  hsize_t stride[4];

  for (int i=0; i<n_dims; ++i) {
    l_nint[i] = d->L_nint[i]; // Selection size, target and destination
    l_ntot[i] = d->L_ntot[i]; // Memory space total size
    l_strt[i] = d->L_strt[i]; // Memory space selection start
    stride[i] = 1;
  }
  l_nint[ndp1 - 1] = 1;
  l_ntot[ndp1 - 1] = n_memb;
  stride[ndp1 - 1] = n_memb;

  // The loop over processors is needed if COW_MPI support is enabled and
  // COW_HDF5_MPI is not. If either COW_MPI is disabled, or COW_HDF5_MPI is
  // enabled, then the write calls occur without the loop.
  // ---------------------------------------------------------------------------
#if (!COW_HDF5_MPI && COW_MPI)
  for (int rank=0; rank<d->cart_size; ++rank) {
    if (rank == d->cart_rank) {
#endif
      hid_t file = H5Fopen(fname, H5F_ACC_RDONLY, d->fapl);
      hid_t memb = H5Gopen(file, gname, H5P_DEFAULT);
      hid_t mspc = H5Screate_simple(ndp1, l_ntot, NULL);
      hid_t fspc = H5Screate_simple(n_dims, G_ntot, NULL);
      for (int n=0; n<n_memb; ++n) {
	hid_t dset = H5Dopen(memb, pnames[n], H5P_DEFAULT);
	l_strt[ndp1 - 1] = n;
	H5Sselect_hyperslab(mspc, H5S_SELECT_SET, l_strt, stride, l_nint, NULL);
	H5Sselect_hyperslab(fspc, H5S_SELECT_SET, G_strt, NULL, L_nint, NULL);
	H5Dread(dset, H5T_NATIVE_DOUBLE, mspc, fspc, d->dxpl, data);
	H5Dclose(dset);
      }
      H5Sclose(fspc);
      H5Sclose(mspc);
      H5Gclose(memb);
      H5Fclose(file);
#if (!COW_HDF5_MPI && COW_MPI)
    }
    if (cow_mpirunning()) {
      MPI_Barrier(d->mpi_cart);
    }
  }
#endif // !COW_HDF5_MPI && COW_MPI
  return 0;
}

//.........这里部分代码省略.........
     *                    0  0  0 59  0 61  0  0  0  0  0  0
     *                    0 25 26  0 27 28  0 29 30  0 31 32
     *                    0 33 34  0 35 36 67 37 38  0 39 40
     *                    0 41 42  0 43 44  0 45 46  0 47 48
     *                    0  0  0  0  0  0  0  0  0  0  0  0
     *
     */

    /*
     * Close memory file and memory dataspaces.
     */
    ret = H5Sclose(mid1);
    ret = H5Sclose(mid2);
    ret = H5Sclose(fid);

    /*
     * Close dataset.
     */
    ret = H5Dclose(dataset);

    /*
     * Close the file.
     */
    ret = H5Fclose(file);

    /*
     * Open the file.
     */
    file = H5Fopen(H5FILE_NAME, H5F_ACC_RDONLY, H5P_DEFAULT);

    /*
     * Open the dataset.
     */
    dataset = H5Dopen(file,"Matrix in file");

    /*
     * Get dataspace of the open dataset.
     */
    fid = H5Dget_space(dataset);

    /*
     * Select first hyperslab for the dataset in the file. The following
     * elements are selected:
     *                     10  0 11 12
     *                     18  0 19 20
     *                      0 59  0 61
     *
     */
    start[0] = 1; start[1] = 2;
    block[0] = 1; block[1] = 1;
    stride[0] = 1; stride[1] = 1;
    count[0]  = 3; count[1]  = 4;
    ret = H5Sselect_hyperslab(fid, H5S_SELECT_SET, start, stride, count, block);

    /*
     * Add second selected hyperslab to the selection.
     * The following elements are selected:
     *                    19 20  0 21 22
     *                     0 61  0  0  0
     *                    27 28  0 29 30
     *                    35 36 67 37 38
     *                    43 44  0 45 46
     *                     0  0  0  0  0
     * Note that two hyperslabs overlap. Common elements are:
     *                                              19 20
     *                                               0 61

/*+++++++++++++++++++++++++
.IDENTifer   PYTABLE_append_array
.PURPOSE     append data to HDF5 dataset, extending the dimension ''extdim''
.INPUT/OUTPUT
  call as    stat = PYTABLE_append_array( locID, dset_name, 
                                          extdim, count, buffer );

     input:
            hid_t locID      :   HDF5 identifier of file or group
	    char  *dset_name :   name of dataset
	    int   extdim     :   dimension to extend
            int   count      :   number of arrays to write
	    void  *buffer    :   data to write
	    
.RETURNS     A negative value is returned on failure. 
.COMMENTS    none
-------------------------*/
herr_t PYTABLE_append_array( hid_t locID, const char *dset_name, 
			     int extdim, int count, const void *buffer )
{
     int      rank;

     hid_t    dataID;
     hid_t    spaceID = -1;
     hid_t    mem_spaceID = -1;
     hid_t    typeID = -1;
     hsize_t  *dims = NULL;
     hsize_t  *dims_ext = NULL;
     hsize_t  *offset = NULL;
     herr_t   stat;

/* open the dataset. */
     if ( (dataID = H5Dopen( locID, dset_name, H5P_DEFAULT )) < 0 ) return -1;

/* get the dataspace handle */
     if ( (spaceID = H5Dget_space( dataID )) < 0 ) goto done;

/* get rank */
     if ( (rank = H5Sget_simple_extent_ndims( spaceID )) < 0 ) goto done;

/* get dimensions */
     dims = (hsize_t *) malloc( rank * sizeof(hsize_t) );
     dims_ext = (hsize_t *) malloc( rank * sizeof(hsize_t) );
     offset = (hsize_t *) calloc( rank, sizeof(hsize_t) );
     if ( H5Sget_simple_extent_dims( spaceID, dims, NULL ) < 0 )
       goto done;
     offset[extdim] = dims[extdim];
     (void) memcpy( dims_ext, dims, rank * sizeof(hsize_t) );
     dims_ext[extdim] = count;
     dims[extdim] += count;

/* terminate access to the dataspace */
     if ( H5Sclose( spaceID ) < 0 ) goto done;

/* extend the dataset */
     if ( H5Dset_extent( dataID, dims ) < 0 ) goto done;

/* select a hyperslab */
     if ( (spaceID = H5Dget_space( dataID )) < 0 ) goto done;
     stat = H5Sselect_hyperslab( spaceID, H5S_SELECT_SET, offset, NULL,
				 dims_ext, NULL );
     free( dims );
     free( offset );
     if ( stat < 0 ) goto done;

/* define memory space */
     if ( (mem_spaceID = H5Screate_simple( rank, dims_ext, NULL )) < 0 )
       goto done;
     free( dims_ext );

/* get an identifier for the datatype. */
     if ( (typeID = H5Dget_type( dataID )) < 0 ) goto done;

/* write the data to the hyperslab */
     stat = H5Dwrite( dataID, typeID, mem_spaceID, spaceID, H5P_DEFAULT, 
		      buffer );
     if ( stat < 0 ) goto done;

/* end access to the dataset */
     if ( H5Dclose( dataID ) ) goto done;

/* terminate access to the datatype */
     if ( H5Tclose( typeID ) < 0 ) goto done;

/* terminate access to the dataspace */
     if ( H5Sclose( mem_spaceID ) < 0 ) goto done;
     if ( H5Sclose( spaceID ) < 0 ) goto done;
     return 0;
 done:
     if ( dims     != 0 ) free( dims );
     if ( dims_ext != 0 ) free( dims_ext );
     if ( offset   != 0 ) free( offset );
     if ( typeID > 0 ) (void) H5Tclose( typeID );
     if ( spaceID > 0 ) (void) H5Sclose( spaceID );
     if ( mem_spaceID > 0 ) (void) H5Sclose( mem_spaceID );
     if ( dataID > 0 ) (void) H5Dclose( dataID );
     return -1;
}

int main(int argc, char ** argv)
{

    if(argc < 2){
        std::cout << "please specify a file" << std::endl;
        return 0;
    }
    std::string filename = argv[1];

    hsize_t offset[2] = {2,3};
    if (argc == 4){
        offset[0] = atoi(argv[2]);
        offset[1] = atoi(argv[3]);
    }

    int m_rows = 4;
    int m_cols = 4; 

    herr_t  status;
    hid_t file = H5Fopen (filename.c_str(), H5F_ACC_RDONLY, H5P_DEFAULT);
    hid_t dset = H5Dopen (file, "DATASET", H5P_DEFAULT);

    hid_t dcpl = H5Dget_create_plist (dset);
    H5D_layout_t layout = H5Pget_layout (dcpl);

    hid_t space = H5Dget_space (dset);
    hsize_t dims[2], mdims[2];
    status = H5Sget_simple_extent_dims(space,dims,mdims);

    int dim1 = dims[0];
    int dim2 = dims[1];

    const int length = m_rows*m_cols;
    double * data = new double[length];

    // Select from the file

    hsize_t count[2] = {4,4};
    status = H5Sselect_hyperslab (space, H5S_SELECT_SET, offset, NULL, count, NULL);

    // Create memory space
    hsize_t dim_out[2] = {m_rows, m_cols};
    hsize_t offset_out[2] = {0,0};
    hsize_t count_out[2] = {m_rows, m_cols};

    hid_t memspace = H5Screate_simple(2,dim_out,NULL);   
    status = H5Sselect_hyperslab(memspace, H5S_SELECT_SET, offset_out, NULL, count_out, NULL);

    status = H5Dread (dset, H5T_NATIVE_DOUBLE, memspace, space, H5P_DEFAULT, data);
    
    // Print to screen
    for(int r=0; r<m_rows; ++r){
        for(int c=0; c<m_cols; ++c){
            std::cout << std::setfill (' ') << std::setw (8);
            std::cout << data[c + r*m_cols];
        }
        std::cout << std::endl;
    }
             
    delete [] data;

    status = H5Pclose (dcpl);
    status = H5Dclose (dset);
    status = H5Sclose (space);
    status = H5Fclose (file);


    return 0;
}

//.........这里部分代码省略.........
	poHparent->pszPath = CreatePath( poHparent );
    }


    switch ( oStatbuf.type ) 
	{
	case H5G_LINK:
	    poHchild->nbAttrs = 0;
	    poHchild->nbObjs = 0;
	    poHchild->poHchild = NULL;
	    poHchild->nRank      = 0;
	    poHchild->paDims    = 0;
	    poHchild->HDatatype = 0;
	    break;
	    
	case H5G_GROUP:
	    if( ( hGroupID = H5Gopen( hHDF5, pszObjName ) ) == -1  ) {
		printf( "Error: unable to access \"%s\" group.\n", 
			pszObjName );
		return -1;
	    }
	    nbAttrs          = H5Aget_num_attrs( hGroupID );
	    ret              = H5Gget_num_objs( hGroupID, &nbObjs );
	    poHchild->nbAttrs= nbAttrs;
	    poHchild->nbObjs = (int) nbObjs;
	    poHchild->nRank      = 0;
	    poHchild->paDims    = 0;
	    poHchild->HDatatype = 0;
	    
	    if( nbObjs > 0 ) {
		poHchild->poHchild =( HDF5GroupObjects * )
		    CPLCalloc( (int)nbObjs, sizeof( HDF5GroupObjects ) );
		memset( poHchild->poHchild,0,
			(size_t) (sizeof( HDF5GroupObjects ) * nbObjs) );
	    }
	    else 
		poHchild->poHchild = NULL;

            if( !HDF5GroupCheckDuplicate( poHparent, oStatbuf.objno ) )
                H5Giterate( hHDF5, pszObjName, NULL, 
                            HDF5CreateGroupObjs,  (void*) poHchild );
            else
                CPLDebug( "HDF5", "avoiding link looping on node '%s'.", 
                          pszObjName );
	    H5Gclose( hGroupID );
	    break;
	    
	case H5G_DATASET:
	    
	    if( ( hDatasetID = H5Dopen( hHDF5, pszObjName ) ) == -1  ) {
		printf( "Error: unable to access \"%s\" dataset.\n", 
		       pszObjName );
		return -1;
	    }
	    nbAttrs      = H5Aget_num_attrs( hDatasetID );
	    datatype     = H5Dget_type( hDatasetID );
	    dataspace    = H5Dget_space( hDatasetID );
	    n_dims       = H5Sget_simple_extent_ndims( dataspace );
	    native       = H5Tget_native_type( datatype, H5T_DIR_ASCEND );
	    
	    if( n_dims > 0 ) {
		dims     = (hsize_t *) CPLCalloc( n_dims,sizeof( hsize_t ) );
		maxdims  = (hsize_t *) CPLCalloc( n_dims,sizeof( hsize_t ) );
	    }
	    status     = H5Sget_simple_extent_dims( dataspace, dims, maxdims );
	    if( maxdims != NULL )
		CPLFree( maxdims );
	    
	    if( n_dims > 0 ) {
		poHchild->nRank     = n_dims;   // rank of the array
		poHchild->paDims    = dims;      // dimmension of the array.
		poHchild->HDatatype = datatype;  // HDF5 datatype
	    }
	    else  {
		poHchild->nRank     = -1;
		poHchild->paDims    = NULL;
		poHchild->HDatatype = 0;
	}
	    poHchild->nbAttrs   = nbAttrs;
	    poHchild->nbObjs    = 0;
	    poHchild->poHchild  = NULL;
	    poHchild->native    = native;
	    ret                 = H5Dclose( hDatasetID );
	    break;
	    
	case H5G_TYPE:
	    poHchild->nbAttrs = 0;
	    poHchild->nbObjs = 0;
	    poHchild->poHchild = NULL;
	    poHchild->nRank      = 0;
	    poHchild->paDims    = 0;
	    poHchild->HDatatype = 0;
	    break;
	    
	default:
	    break;
	}
    
    return 0;
}

int
main (void)
{
    hid_t               file, space, memspace, dset, dset2, attr;
                                                    /* Handles */
    herr_t              status;
    hsize_t             dims[1] = {DIM0},
                        dims2[2] = {DS2DIM0, DS2DIM1},
                        coords[4][2] = { {0,  1},
                                         {2, 11},
                                         {1,  0},
                                         {2,  4} },
                        start[2] = {0, 0},
                        stride[2] = {2, 11},
                        count[2] = {2, 2},
                        block[2] = {1, 3};
    hssize_t            npoints;
    hdset_reg_ref_t     wdata[DIM0],                /* Write buffer */
                        *rdata;                     /* Read buffer */
    ssize_t             size;
    char                wdata2[DS2DIM0][DS2DIM1] = {"The quick brown",
                                                    "fox jumps over ",
                                                    "the 5 lazy dogs"},
                        *rdata2,
                        *name;
    int                 ndims,
                        i;

    /*
     * Create a new file using the default properties.
     */
    file = H5Fcreate (FILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);

    /*
     * Create a dataset with character data.
     */
    space = H5Screate_simple (2, dims2, NULL);
    dset2 = H5Dcreate (file, DATASET2, H5T_STD_I8LE, space, H5P_DEFAULT,
                H5P_DEFAULT, H5P_DEFAULT);
    status = H5Dwrite (dset2, H5T_NATIVE_CHAR, H5S_ALL, H5S_ALL, H5P_DEFAULT,
                wdata2);

    /*
     * Create reference to a list of elements in dset2.
     */
    status = H5Sselect_elements (space, H5S_SELECT_SET, 4, coords[0]);
    status = H5Rcreate (&wdata[0], file, DATASET2, H5R_DATASET_REGION, space);

    /*
     * Create reference to a hyperslab in dset2, close dataspace.
     */
    status = H5Sselect_hyperslab (space, H5S_SELECT_SET, start, stride, count,
                block);
    status = H5Rcreate (&wdata[1], file, DATASET2, H5R_DATASET_REGION, space);
    status = H5Sclose (space);

    /*
     * Create dataset with a null dataspace to serve as the parent for
     * the attribute.
     */
    space = H5Screate (H5S_NULL);
    dset = H5Dcreate (file, DATASET, H5T_STD_I32LE, space, H5P_DEFAULT,
                H5P_DEFAULT, H5P_DEFAULT);
    status = H5Sclose (space);

    /*
     * Create dataspace.  Setting maximum size to NULL sets the maximum
     * size to be the current size.
     */
    space = H5Screate_simple (1, dims, NULL);

    /*
     * Create the attribute and write the region references to it.
     */
    attr = H5Acreate (dset, ATTRIBUTE, H5T_STD_REF_DSETREG, space, H5P_DEFAULT,
                    H5P_DEFAULT);
    status = H5Awrite (attr, H5T_STD_REF_DSETREG, wdata);

    /*
     * Close and release resources.
     */
    status = H5Aclose (attr);
    status = H5Dclose (dset);
    status = H5Dclose (dset2);
    status = H5Sclose (space);
    status = H5Fclose (file);


    /*
     * Now we begin the read section of this example.  Here we assume
     * the attribute has the same name and rank, but can have any size.
     * Therefore we must allocate a new array to read in data using
     * malloc().
     */

    /*
     * Open file, dataset, and attribute.
     */
    file = H5Fopen (FILE, H5F_ACC_RDONLY, H5P_DEFAULT);
    dset = H5Dopen (file, DATASET, H5P_DEFAULT);
//.........这里部分代码省略.........

//.........这里部分代码省略.........
                        H5Tset_size(atype, 4);
                        hid_t  attr3 = H5Acreate1(channelgroup, "type", atype, aid3, H5P_DEFAULT);
                        status = H5Awrite(attr3, atype,"dict");
                        H5Aclose(attr3);
                        H5Tclose(atype);
                        H5Sclose(aid3);




                    }
                    if (channelgroup!=0)
                    {

                        QList<QString> keys2=(*events)[keys1[i]].keys();
                        for (int i2=0;i2<keys2.length();i2++)
                        {
                            QString dname = QString("keystr_%1").arg(keys2[i2]);
                            datasetlength = (*events)[keys1[i]][keys2[i2]].length();

                            if (datasetlength>0)
                            {

                                //Try to open dataset if it exists

                                //turn off errors when we query the group, using open
                                hid_t error_stack = H5Eget_current_stack();
                                H5E_auto2_t  oldfunc;
                                void *old_client_data;
                                H5Eget_auto(error_stack, &oldfunc, &old_client_data);
                                H5Eset_auto(error_stack, NULL, NULL);

                                //query or open dataset
                                curdataset = H5Dopen(channelgroup,dname.toStdString().c_str(),H5P_DEFAULT);

                                //turn errors back on.
                                H5Eset_auto(error_stack, oldfunc, old_client_data);

                                //if cannot open dataset, create it, and make it chunked.
                                if (curdataset<=0)
                                {

                                    //set up size info, chunks etc...

                                    maxdims[0]=H5S_UNLIMITED;
                                     rank = 1;
                                    d_dims[0]=datasetlength;

                                    curdataspace=  H5Screate_simple(rank, d_dims,maxdims);


                                     prop = H5Pcreate(H5P_DATASET_CREATE);
                                    status = H5Pset_chunk(prop, rank, d_dims);

                                    if (status) trap();

                                    curdataset = H5Dcreate(
                                        channelgroup,
                                        dname.toStdString().c_str(),
                                        H5T_NATIVE_FLOAT,
                                        curdataspace,
                                        H5P_DEFAULT,
                                        prop,
                                        H5P_DEFAULT);