Published: Jan 12, 2024 by Peter Hill
Project info
nc-complex is a lightweight, drop-in extension for netCDF that
handles reading and writing complex numbers. Currently there are C and
C++ APIs, and it has been integrated into netcdf4-python. A
Fortran API is also planned.
The nc-complex library understands most of the major existing
conventions
for storing complex numbers, including as a compound datatype or as a
dimension of size two, and should work for any netCDF file format.
I wrote nc-complex as I was getting frustrated with the lack of
native support for complex numbers in netCDF files, leading to people
using a whole variety of different ways of storing them. The netCDF
developers were not very keen on expanding their specification to
include complex numbers, despite users requesting them for a decade or
more. This is also at least partly due to HDF5 also not having
native support for complex numbers.
This project was partly about this new library that I wrote, but also
partly a campaign to try and get better support for complex numbers
into these popular file formats. To this end, I wrote a reasonably
comprehensive discussion of the issue in the nc-complex readme, and
provided input into discussions in the CF-conventions
and HDF5 communities. The outcome of this was getting a proposal
accepted for getting native complex number support into HDF5,
hopefully opening the possibility for eventual native support in
netCDF as well.