On 18/08/11 20:49, John Knutson wrote: > In my own work, I use pre-sized datasets with compound types. Our data > are not homogeneous, so the compound types are pretty much required. > The pre-sized datasets affords us the ability to actively index the data > on read and write, which is of particular value on the read-side where > knowing exactly where to find the data you want is highly valuable. > > If, on the other hand, you just need to store data that you're never > going to do partial reads of, packet tables are easier to implement.
Dear John, thank you very much for your hints. Partial reads and absolute performances are not critical for my application. I think I'll give packet tables a try. On the other hand, easily accessing the data from Python and Matlab is a requirement. Are packet tables (or the underlying structures) accessible in an easy way from Matlab? Python has the h5py library, which, if it is not already capable of handling packet tables, should be not too difficult to extend. A while back I investigated the kind of data structure used by PyTables, which offers the kind of functionality I'm interested in. From my aproximative knowledge of HDF5, I understood that it uses a "custom" version of HDF5 Tables which support chunked writes. However I need compatibility with Matlab and the ability of writing those files from a C library. How such a structure compares with packed tables? Thank you. Cheers, -- Daniele _______________________________________________ Hdf-forum is for HDF software users discussion. [email protected] http://mail.hdfgroup.org/mailman/listinfo/hdf-forum_hdfgroup.org
