How to list all datasets in h5py file?

You have to use the keys method. This will give you a List of unicode strings of your dataset and group names. For example: Datasetnames=hf.keys() Another gui based method would be to use HDFView. https://support.hdfgroup.org/products/java/release/download.html

Experience with using h5py to do analytical work on big data in Python?

We use Python in conjunction with h5py, numpy/scipy and boost::python to do data analysis. Our typical datasets have sizes of up to a few hundred GBs. HDF5 advantages: data can be inspected conveniently using the h5view application, h5py/ipython and the h5* commandline tools APIs are available for different platforms and languages structure data using groups … Read more

How to overwrite array inside h5 file using h5py

You want to assign values, not create a dataset: f1 = h5py.File(file_name, ‘r+’) # open the file data = f1[‘meas/frame1/data’] # load the data data[…] = X1 # assign new values to data f1.close() # close the file To confirm the changes were properly made and saved: f1 = h5py.File(file_name, ‘r’) np.allclose(f1[‘meas/frame1/data’].value, X1) #True

Is there an analysis speed or memory usage advantage to using HDF5 for large array storage (instead of flat binary files)?

HDF5 Advantages: Organization, flexibility, interoperability Some of the main advantages of HDF5 are its hierarchical structure (similar to folders/files), optional arbitrary metadata stored with each item, and its flexibility (e.g. compression). This organizational structure and metadata storage may sound trivial, but it’s very useful in practice. Another advantage of HDF is that the datasets can … Read more

Input and output numpy arrays to h5py

h5py provides a model of datasets and groups. The former is basically arrays and the latter you can think of as directories. Each is named. You should look at the documentation for the API and examples: http://docs.h5py.org/en/latest/quick.html A simple example where you are creating all of the data upfront and just want to save it … Read more