Quincey Koziol from the HDF5 Group visited the LOFAR crew at the UvA on Thursday-Friday (Sept. 9-10th). The agenda is listed below. We gave Quincey an overview of LOFAR along with an introduction to the LOFAR data format/structures from the Interface Control Documents (ICDs). All presentations are attached below. Quincey's HDF5 presentations can also be found below.
Participants:
HDF5 Group Member - Quincey Koziol
Attendees - Anastasia Alexov, Ken Anderson, John Swinbank, Lars Baehren, Micheal Wise, Adriaan Renting, Ger van Diepen, Tom Bennett (South Africa via EVO)
tools which exist for HDF5 (other than HDFView, h5py, pytables)
CONCERNS:
Speed when using smallish hyperslabs
Robustness. E.g. What happens if a system crashes after writing some hours of data? What are the chances that all data are lost? What impact has robustness on performance?
The future of the C++ interface.
Is HDF5 always backward compatible? I.e. can a file created with HDF5 1.8 always be read with newer versions, even a hypothetical version 2.1 (AFAIK HDF5 1.8 is not backward compatible with 1.6). The same for building the software.
Is it more efficient to store data in:
One table per subband (N x 1-dimensional tables in one Group)
One table for all subbands (1 x N-dimensional table in one Group)
1 Array per Subband (N x 1-dimensional array in one Group)
1 Array for all Subbands (1 x N-dimensional array in one Group)