Documentation is not clear on how to install metpy without the pyproj dependency

[wxmann]

What can be better?

I'm trying to deploy an API implemented in Python that leverages Metpy for some calculations and unit transformations behind the scenes. I am using poetry instead of conda as my package manager, and by doing so when I try to add Metpy to my project I'm receiving various environment issues related to pyproj and proj.

The README.md indicates that pyproj is an optional dependency, which makes sense, because as I mentioned above I just want to use metpy to do some calculations. But then it links to the Installation Guide, which has no mention about how to install Metpy without pyproj. Are there explicit instructions on how to install Metpy without pyproj to bypass environment issues in non-Conda situations?

[DWesl]

Poetry would be getting its information here:

MetPy/pyproject.toml

Lines 28 to 38 in d48a0fc

	dependencies = [
	"matplotlib>=3.5.0",
	"numpy>=1.22.0",
	"pandas>=1.4.0",
	"pint>=0.17",
	"pooch>=1.2.0",
	"pyproj>=3.3.0",
	"scipy>=1.8.0",
	"traitlets>=5.1.0",
	"xarray>=2022.6.0"
	]

Since pyproj is in the project.dependencies section rather than the project.optional-dependencies one, poetry will always try to install pyproj. With pip, I would install the rest of the dependencies in that list, then install MetPy without dependencies, that is:

pip install "matplotlib>=3.5.0" "numpy>=1.22.0" "pandas>=1.4.0" "pint>=0.17" "pooch>=1.2.0" "scipy>=1.8.0" "traitlets>=5.1.0" "xarray>=2022.6.0"
pip install --no-deps metpy

python-poetry/poetry#3377 suggests poetry doesn't have an equivalent option

[dopplershift]

pyproj has been a required dependency since 53776c1, so unfortunately the only thing to do here is update the README to reflect the current set of dependencies.

I'm curious what problems you're running into with pyproj/PROJ? In my experience those aren't usually too problematic.