Merge branch 'conda_instal' of github.com:LSSTDESC/CLMM into conda_in…

…stal

CONTRIBUTING.md

@@ -115,11 +115,44 @@ All these steps should be done on the `publish-docs` branch (just `git checkout
 3. From the `main` CLMM directory (the one that contains `setup.py`) run `./publish_docs` (note, this is different from `./update_docs` that you did in your development branch) and it does all of the work for you (including automatically pushing changes to Github)!
 
 ## Creating installation via pip and conda <a name="creating_pip_conda"></a>
-
-To create an installation via `pip`...
-
-To create an installation via `conda`...
-
+After new changes to the main code have been made, you will want to update the existing clmm package at the Pypi repository to create an installation via `pip`. To do so, the following steps must be followed:
+1. First, install the `hatch` package with pip with the following command:
+    ```bash
+    pip install hatch
+    ```
+You can check [Publish your Python package with Hatch](https://www.pyopensci.org/python-package-guide/tutorials/publish-pypi.html) for more information.
+2. In the `CLMM` repository, create the virtual environment with the command:
+    ```bash
+    cd CLMM
+    hatch env create
+    ```
+3. If new packages are required as dependencies, add the packages to the `pyproject.toml` file in the repository in the dependencies section. The installation files will be generated from this file, so if any changes are required, look carefully inside the `pyproject.toml` file for the sections related to the changes.
+4. Next, build the needed files for publication with the command:
+    ```bash
+    hatch build
+    ```
+This will create a `clmm-1.14.4.tar.gz` and `clmm-1.14.4-py3-none-any.whl` files in the `dist` folder inside the repository. Note that the name of the files will change for the given version to be publicated.
+5. To publish the package to pip, we will use `twine`, which should be installed with the following:
+    ```bash
+    pip install twine
+    ```
+6. To make sure that the package is working properly, we can first publish `clmm` to `PypiTest` running the command:
+    ```bash
+    twine upload --repository testpypi dist/* --verbose
+    ```
+Once the package is published, one can install it by running:
+    ```bash
+    pip install -i https://test.pypi.org/simple/ clmm==1.14.4 --extra-index-url https://pypi.org/simple clmm==1.14.4
+    ```
+with the proper version number. This step will require an account at [PypiTest](https://test.pypi.org/) and you will need to generate a token that is required to publish packages. Note that some of the required dependencies may note be published to `PypiTest` and thus we need the extra index url to import the packages from `Pypi`. If the package was properly installed, we are now ready to publish it to `Pypi`.
+7. To publish to `Pypi`, run the command:
+```bash
+twine upload dist/*
+``` 
+This last step must be done with the token used to publish `CLMM` from the right account at `Pypi`. Once this is done, you will find the latest version of `CLMM` at the `Pypi` repository. To test it, try running
+```bash
+pip install clmm
+```
 ## Additional resources <a name="additional_resources"></a>
 
 Here's a list of additional resources which you may find helpful in navigating git for the first time.