The Feather file format is a column-oriented binary disk-based format based on Apache Arrow and supported by (at least) Python, R and Julia. Some description of it is available at https://github.com/wesm/feather and https://blog.rstudio.com/2016/03/29/feather/. It can be used for large datasets, but it does not support array-valued columns. It can be a useful format to use for exchanging data with R, for which FITS I/O is reported to be slow.
This writer is somewhat experimental; please report problems if you encounter them.
If no output format is explicitly chosen,
writing to a filename with
the extension ".fea
" or ".feather
" (case insensitive)
will select feather
format for output.