Updates to 0.21

[cako]

Update versions to avoid segfaults, and updates to v0.21. In addition, it drops support for Python 3.6 and introduces a [dev] extras.

Previous to this version, incompatibilities between pybind11, scipy and possibly other libraries were causing segfaults to the CurveLab code at times. While this is not yet 100% understood, this PR appears to avoid segfaults on tested versions.

This version has been checked on Ubuntu 22.04 with the conda for versions 3.7, 3.8, 3.9, 3.10, 3.11 as follows:

export FFTW=...
export FDCT=...
conda create -n py3.X python=3.X  # `-c conda-forge` if Python 3.11
conda activate py3.X
conda install -c conda-forge pylops  # `pip install pylops` if Python 3.11
git clone --branch patch-versions https://github.com/PyLops/curvelops.git
cd curvelops
python3 -m pip install -e ./[dev]
pytests

In addition, it has been tested in the same machine and for the same versions using venv as follows:

export FFTW=...
export FDCT=...
sudo apt install python3.X python3.X-dev python3.X-distutils  # Older versions may not be available in the default repos
virtualenv venv3X --python=python3.X
source venv3X/bin/activate
git clone --branch patch-versions https://github.com/PyLops/curvelops.git
cd curvelops
python3 -m pip install -e ./[dev]
pytests

CurveLab and FFTW were compiled on gcc and g++ versions g++ 11.3.0, GLIBC version 2.35.

If segfaults are still happening (I did not experience any), one may try the following procedure:

1. Comment out all lines with fftwnd_destroy_plan in
   • CurveLab-2.1.3/fdct_wrapping_cpp/src/fdct_wrapping.cpp
   • CurveLab-2.1.3/fdct_wrapping_cpp/src/ifdct_wrapping.cpp
   • CurveLab-2.1.3/fdct3d/src/fdct3d.cpp
   • CurveLab-2.1.3/fdct3d/src/fdct3d_forward.cpp
   • CurveLab-2.1.3/fdct3d/src/fdct3d_inverse.cpp
2. Recompile CurveLab, e.g., cd CurveLab-2.1.3/ && make clean && make
3. Rebuild/install curvelops e.g., pip install -e .
4. Be aware that this creates possible memory leaks.

[mrava87]

Thanks a lot, this looks great!

I just gave a few minor comments, also I will try using the commands you provide on my linux machine and report back in coming days :)

[mrava87]

I confirm, the new installation process works for me as well with Ubuntu 18.04.6. Feel free to merge :)