title: Appending data to the same dataset in hdf5 in matlab
body: <p>I have to put all the huge data together into a single dataset in hdf5. Now, the thing is, if you try:</p>
  
  <pre><code>&gt;&gt; hdf5write('hd', '/dataset1', [1;2;3])
  &gt;&gt; hdf5write('hd', '/dataset1', [4;5;6], 'WriteMode', 'append')
  ??? Error using ==&gt; hdf5writec
  writeH5Dset: Dataset names must be unique when appending data.
  </code></pre>
  
  <p>As you can see, hdf5write will complain when you tried to append data to the same dataset. I've looked around and see one possible workaround is to grab your data from the dataset first, then concatenate the data right in matlab environment. This is not a problem for small data, of course. For this case, we are talking about gigabytes of data, and Matlab starts yelling out out of memory.</p>
  
  <p>Because of this, what are my available options in this case?</p>
  
  <p>Note: we do not have h5write function in our matlab version. </p>