mar-pull.md

@@ -9,7 +9,7 @@ In this tutorial, you will learn how you can get only a subset of files and/or f
 
 ## Prerequisites
 
-First of all, make sure ``git`` is available on the computer where you want to synchronize your ``~/MAR`` folder with a repository from this GitLab group. You do not necessarily need the latest version, but make sure to have at the very least [version 2.25](https://github.blog/open-source/git/highlights-from-git-2-25/), which comes with ``git sparse-checkout``, a command which you may want to use later.
+First of all, make sure ``git`` is available on the computer where you want to synchronize your ``~/MAR`` folder with a repository from this GitLab group. You do not necessarily need the latest version, but make sure to have at the very least [version 2.25](https://github.blog/open-source/git/highlights-from-git-2-25/), which comes with ``git sparse-checkout``, a useful command which will simplify updating your _sparse checkout_.
 
 Second, on the same computer, run this command:
 
@@ -59,12 +59,26 @@ git pull origin main
 
 ## Updating your repository again
 
-If you did all previous steps correctly, the next time you want to update, you will only need to run the final command from the previous section (while in `~/MAR`).
+If you followed all previous steps correctly, the next time you want to update, you will only need to run the final command from the previous section (while in `~/MAR`).
 
 ```
 git pull origin main
 ```
 
+## Restoring repository code (undo local changes)
+
+Let us assume you pulled the contents of `src/forMAR/forMAR` from [ESPECES/MAR/stable](https://gitlab.uliege.be/especes/mar/stable) in your `~/MAR` folder, as suggested earlier, and modified a few files in your own `~/MAR/src/forMAR/forMAR` folder to prepare a MAR executable.
+
+For example, you modified `src/forMAR/forMAR/mar_ecrad_mod.f90` or `src/forMAR/forMAR/marmagic_mod.f90` to tune model parameters, or changed `src/forMAR/forMAR/mar_ib_mod.f90` to change the outputs (e.g., to produce hourly outputs instead of daily outputs).
+
+However, you now want to revert these local changes, either to tune a new MAR executable or to update your copy without having conflicts. You can then use the next ``git`` command.
+
+```
+git restore src/forMAR/forMAR
+```
+
+The syntax is ``git restore [path]`` where ``[path]`` (a mandatory argument) can be either a single file or a whole folder. In the above example, we restore the entirety of ``src/forMAR/forMAR`` from the remote repository.
+
 ## Adding other paths to the _sparse checkout_
 
 If you want to expand your _sparse checkout_ to get other parts of a repository, you can edit `.git/info/sparse-checkout` (e.g., with ``vim`` or ``gedit``) in the folder where you initialized ``git`` (`~/MAR`, in this case) and add more paths or patterns. The `.git/info/sparse-checkout` file itself is interpreted by ``git`` more or less in the same way as a ``.gitignore`` file.