Hi there,


I have a Java process that writes HDF5 files with the following
approximate structure:

group "xxx" {

    group "yyy" {

        dataset {}
        dataset {}

    }

    group "zzz" {

        dataset {}
        dataset {}

    }

}

where dataset is a rank one dataspace having a compound datatype defined as:

H5T_UNIX_TIME, float, float, float, float

I have tried R packages h5r and hdf5 in an attempt to read the file
but examining the source of h5r and reading documentation for hdf5
here:  http://xweb.geos.ed.ac.uk/~hcp/Rhdf5.html  leads me to believe
that compound datatypes are not supported by these packages.  My guess
is that mapping arbitrary type definitions in HDF5 to available types
in R might be somewhat tricky.  Incidentally, h5dump has trouble
displaying the data in the dataset but I think this is to do with the
time 'field':

      DATASPACE  SIMPLE { ( 33 ) / ( H5S_UNLIMITED ) }
      DATA {
         h5dump error: unable to print data
      }

Since I am new to both HDF5 and R I wonder if there are better
approaches to storing the information I have that will allow me to use
either h5r or hdf5 packages unmodified.  I expect I can contribute
changes to either of the packages that will allow me to do what I
describe but fall short of general compound datatype support.

Any comments or advice gratefully received.

Regards...Jeremy

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