MATLAB: How to write and read logical data types to the HDF5 data file in MATLAB 7.8 (R2009a)

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I am using HDF5 low-level functions to write data to an HDF5 file. I would like to save my MATLAB LOGICAL array to HDF5. I have tried using the following code:

fid = H5F.create('myhdf5.h5','H5F_ACC_TRUNC','H5P_DEFAULT','H5P_DEFAULT');
dspace = H5S.create_simple(1,10,10);
dset = H5D.create(fid,'BoolTest','H5T_NATIVE_HBOOL',dspace,'H5P_DEFAULT');
H5D.write(dset,'H5T_NATIVE_HBOOL','H5S_ALL','H5S_ALL','H5P_DEFAULT',rand(10,1));
H5D.close(dset);
H5S.close(dspace);
H5F.close(fid)

However this fails with the error:

 ??? Error using ==> hdf5lib2
 Incorrect type of array passed
 to H5D.write in conjunction with
 the specified memory datatype.
 Error in ==> H5D.write at 37
 H5ML.hdf5lib2('H5Dwrite',
 varargin{:});

Best Answer

HDF5 1.8.x does not support a boolean datatype. To work around this, use an integer type and interpret your data according to your rules.

For more information see the HDF5 FAQ by doing an internet search for: "HDF5 faq boolean".

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MATLAB: Do I get an error from the HDF5 library when I try to create an HDF5 dataset with one of the dimensions set to ‘H5S_UNLIMITED’ in MATLAB

This error occurs because if 'H5S_UNLIMITED' is specified for one of the dataset dimensions, the dataset must be chunked rather than contiguous. To resolve the error, one can simply define the dataset creation property list to specify that the dataset should be chunked. For the example in the question, this can be done as follows:

dims       = [60 30 10];
maxdims    = {dims(1), dims(2), 'H5S_UNLIMITED'};
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Best Answer

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MATLAB: How to make array from characters from variables

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