docs: add an example for updating namelists

Author: AlexandreMary

Diff for: docs/pages.jl

@@ -18,6 +18,7 @@ pages = [
         "Investigate Problems" => "investigatingproblems.md",
         "Build options" => "buildoptions.md",
         "Input data" => "inputdata.md",
+        "Update namelists" => "uget/update_namelists.md",
         "Other options" => "otheroptions.md",
         "User configuration" =>  "userconfiguration.md",
         "Parallel profiling" => "parallelprofiling.md",

Diff for: docs/src/uget/uget.md

@@ -1,7 +1,5 @@
 # User Documentation Uenv/Uget
 
-Alexandre Mary et al.
-
 The *uenv/uget* tool developped in Vortex is the counterpart of
 *genv/gget* (MF/GCO op team), but user-oriented (hence the **u** instead
 of **g**) and shareable with other users. It enables, in Vortex
@@ -20,9 +18,9 @@ use it properly.
 The following example shows how to modify components of an Arome-France
 *genv* catalog and modify its components piece by piece.
 
-### Before first use
+### Before first use {#uget-first-use}
 
-- load Genv/Gget (in your *profile*, if not already done):
+- on `belenos`, load Genv/Gget (in your *profile*, if not already done):
 
   ```bash
   export PATH=/home/mf/dp/marp/gco/public/bin:$PATH

Diff for: docs/src/uget/update_namelists.md

@@ -0,0 +1,35 @@
+# Uget usecase: update namelists for Davai
+
+In this example, we need to update namelists of Davai for the needs of a code modification
+(e.g. renaming of a variable, or adding a new block).
+Cf. "uget" section of this documentation for installation and a more thorough tutorial.
+
+#### Setup a custom catalogue
+
+The "uenv's" or catalogues of static input resources used by Davai are listed in the `conf/davai_nrv.ini` config file
+of the experiment.
+For instance, in `cy49.davai_specials.02@davai` is to be found a package of namelists.
+We first create a local copy of this catalogue with:
+
+```
+uget.py hack env cy49.davai_specials.02@davai into cy49.davai_specials.02@@${USER}
+```
+
+This will create a local catalogue file under `~/.vortexrc/hack/uget/${USER}/env/`.
+Make sure to modify the value in `davai_nrv.ini` to use your local copy.
+
+#### Edit namelists
+
+We then create a local copy of the namelist package listed in this catalogue `[email protected]@davai`:
+
+```
+uget.py hack data [email protected]@davai into [email protected]@${USER}
+```
+
+This creates a tgz file under `~/.vortexrc/hack/uget/${USER}/data/`, which then needs to be unpacked.
+Make sure to modify the catalogue file to use your local copy of the namelists.
+
+You then can modify existing namelist files in the unpacked directory.
+
+If your changes are required to run a contribution to IAL, don't forget to provide your catalogue and namelist package
+(paths) in your IAL Pull Request.