MATLAB Programming

Hierarchical Data Format (HDF5) Files
Note Because HDF5 stores data in row-major order and MATLAB
accesses data in column-major order, you should permute your data before
writing it to the file.
data_perm = permute(testdata,[3 2 1]);
H5D.write(datasetID,'H5ML_DEFAULT','H5S_ALL','H5S_ALL', ...
'H5P_DEFAULT',data_perm);
5 Close the data set, data space, data type, and file objects. If used inside a
MATLAB function, these identifiers are closed automatically when they
go out of scope.
H5D.close(datasetID);
H5S.close(dataspaceID);
H5T.close(datatypeID);
H5F.close(fileID);
6 To read the data set you wrote to the file, you must open the file. In HDF5,
you use the H5Fopen routinetoopenanHDF5file,specifyingthenameof
the file, the access mode, and a property list as arguments. The example
uses the corresponding MATLAB function, H5F.open, openingthefilefor
read-only access.
fileID = H5F.open(filename,'H5F_ACC_RDONLY','H5P_DEFAULT');
7 After opening the file, you must open the data set. In HDF5, you use the
H5Dopen function to open a data set. The example uses the corresponding
MATLAB function, H5D.open, specifying as arguments the file ID and the
name of the data set, defined earlier in the example.
datasetID = H5D.open(fileID, dsetname);
8 After opening the data set, you can read the data into the MATLAB
workspace. In HDF5, you use the H5Dread function to read an HDF5
file. The example uses the corresponding MATLAB function, H5D.read,
specifying as arguments the data set ID, the memory data type ID, the
memory space ID, the data space ID, and the transfer property list ID.
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