[Solved] Install matplotlib / basemap in macOS

I have been trying to import the basemap module in my python script using "from mpl_toolkits.basemap import Basemap" but with no luck! I ran into issues while installing basemap with pip. Excerpt from the error:

  Installing build dependencies ... error

  error: subprocess-exited-with-error

  

  × pip subprocess to install build dependencies did not run successfully.

  │ exit code: 1

  ╰─> [552 lines of output]

      Ignoring numpy: markers 'python_version >= "3.10"' don't match your environment

      Ignoring numpy: markers 'python_version == "2.6" or (python_version >= "3.2" and python_version <= "3.3")' don't match your environment

      Ignoring cython: markers 'python_version == "3.2"' don't match your environment

...

...

        note: This error originates from a subprocess, and is likely not a problem with pip.

      error: legacy-install-failure

      

      × Encountered error while trying to install package.

      ╰─> numpy

      

      note: This is an issue with the package mentioned above, not pip.

      hint: See above for output from the failure.

      WARNING: There was an error checking the latest version of pip.

      [end of output]

  

  note: This error originates from a subprocess, and is likely not a problem with pip.

error: subprocess-exited-with-error

× pip subprocess to install build dependencies did not run successfully.

│ exit code: 1

╰─> See above for output.

note: This error originates from a subprocess, and is likely not a problem with pip.

WARNING: There was an error checking the latest version of pip.

So I did a little digging and searched for necessary packages to compile and install basemap on macOS from the source. I have Python 3.9 and macOS 12.4. Here are the steps that worked for me:

• brew install matplotplusplus
• brew install numpy
• brew install proj
• brew install geos
• export GEOS_DIR="/usr/local/Cellar/geos/3.10.3/"
• pip3 install cython
• pip3 install numpy
• git clone https://github.com/matplotlib/basemap.git
• cd basemap
• cd packages
• cd basemap
• python3 setup.py install
• cd ..
• cd basemap_data
• python3 setup.py install
• cd ..
• cd basemap_data_hires
• python3 setup.py install
• cd ..
• cp -R basemap_data/ /usr/local/lib/python3.9/site-packages/mpl_toolkits/basemap_data/