Hi, I was referring to features in HDF5. Looks like these pages in their docs might help:
https://www.hdfgroup.org/HDF5/doc/RM/RM_H5P.html#Property-SetNbit https://www.hdfgroup.org/HDF5/doc/UG/HDF5_Users_Guide-Responsive%20HTML5/#t=HDF5_Users_Guide%2FDatasets%2FHDF5_Datasets.htm%23TOC_5_6_1_Using_the_N_bitbc-21&rhtocid=5.4.0_1 From: Hdf-forum [mailto:[email protected]] On Behalf Of David Sent: 11 February 2016 16:10 To: HDF Users Discussion List Subject: Re: [Hdf-forum] Boolean values Daniel: What are the N-bit type and filter and types you are referring to? Do you mean something I would write or are you talking about something in HDF5? Also can anyone explain how H5T_NATIVE_B8 is different from H5T_NATIVE_UINT8. On Thu, Feb 11, 2016 at 1:29 AM, Daniel Tetlow <[email protected]<mailto:[email protected]>> wrote: You could try making your dataset using an N-bit type based on a copy of an 8-bit type, and then using the N-bit filter. You can then end up handling each Boolean value as a byte in memory, but they’re stored more compactly on disk. Might even compress well too. Dan From: Hdf-forum [mailto:[email protected]<mailto:[email protected]>] On Behalf Of [email protected]<mailto:[email protected]> Sent: 10 February 2016 21:23 To: HDF Users Discussion List Subject: Re: [Hdf-forum] Boolean values I don’t think the hdf Boolean is any different than an integer. If you create a Boolean dataset and query the type, it comes back that it’s an int. You can’t tell after the fact that the data was specified as Boolean. I suppose you can create a packed Boolean type, but you’ll have to do the grunt work of muxing and de-muxing the Booleans. Ultimately, I stuck my bools in separate sbytes. From: Hdf-forum [mailto:[email protected]] On Behalf Of David Sent: Wednesday, February 10, 2016 4:12 PM To: HDF Users Discussion List Subject: [Hdf-forum] Boolean values Is there a way to read/write compact boolean or bitfield values? I see the bitfield types but I can't understand how it's different than writing ints. The API examples show hand packing/unpacking of the bits. How is H5T_NATIVE_B8 different from H5T_NATIVE_UINT8? Ideally I'd like 8-bit bools in memory packed into 1-bit bools on disk so it's easy to work with when loaded but stored compactly. Thanks, David _______________________________________________ Hdf-forum is for HDF software users discussion. [email protected]<mailto:[email protected]> http://lists.hdfgroup.org/mailman/listinfo/hdf-forum_lists.hdfgroup.org Twitter: https://twitter.com/hdf5
_______________________________________________ Hdf-forum is for HDF software users discussion. [email protected] http://lists.hdfgroup.org/mailman/listinfo/hdf-forum_lists.hdfgroup.org Twitter: https://twitter.com/hdf5
