On Thu, Apr 20, 2017 at 12:05 PM, Stephan Hoyer <shoyer@gmail.com> wrote:
> On Thu, Apr 20, 2017 at 11:53 AM, Robert Kern <robert.kern@gmail.com> wrote:
>> I don't know of a format off-hand that works with numpy uniform-length strings and Unicode as well. HDF5 (to my recollection) supports arrays of NULL-terminated, uniform-length ASCII like FITS, but only variable-length UTF8 strings.
> HDF5 supports two character sets, ASCII and UTF-8. Both come in fixed and variable length versions:
> https://github.com/PyTables/PyTables/issues/499
> https://support.hdfgroup.org/HDF5/doc/Advanced/UsingUnicode/index.html
> "Fixed length UTF-8" for HDF5 refers to the number of bytes used for storage, not the number of characters.

Ah, okay, I was interpolating from a quick perusal of the h5py docs, which of course are also constrained by numpy's current set of dtypes. The NULL-terminated ASCII works well enough with np.string's semantics.

Robert Kern