Add installation documentation

docs/index.md

@@ -1,6 +1,7 @@
 ![PowSyBl Logo](_static/logos/logo_lfe_powsybl.svg)
 # PowSyBl Metrix
 
+## Presentation
 
 [MappingTool](mapping.md) provides a mapping configuration from csv timeseries to network.
 This configuration allows to generate iidm network at specified times. Furthermore,
@@ -11,6 +12,113 @@ networks generated by the mapping tool. Its outputs are completed by synthesis.
 
 MetrixTool calls *[metrix simulator](metrix-simulator.md)* as an external program. This program has its own requirements.
 
+## Installation
+
+PowSyBl-Metrix can be installed easily in just a few steps, so that you can use it in command line:
+
+### Downloads
+
+First, on [the release page](https://github.com/powsybl/powsybl-metrix/releases), you can download: 
+
+* itools-metrix
+* metrix-simulator
+
+*itools-metrix* is written in Java, so there is only one version per release, and it works for
+every OS. *metrix-simulator* however is written in C++ so you will need to
+choose the version corresponding to your OS.
+
+Note: Current versions of *metrix-simulator-ubuntu* were compiled on Ubuntu 24. If
+you encounter issues regarding the compiler, don't hesitate to use the *metrix-simulator-centos*
+version that has been compiled with an older version of the compiler.
+
+Once the two zip are downloaded, unzip them in a repository of your choosing.
+
+### Configuration
+
+#### itools command
+
+Now we need to make the *itools* command available. For this, you need to add itools to your PATH.
+
+On Linux, you can for example do this by adding a few lines in your `.bashrc` file (or equivalent):
+
+```shell
+# PowSyBl-Metrix itools repository
+export POWSYBL_METRIX_HOME=<repository_where_you_unzipped_itools-metrix>
+# Add the repository to the path
+export PATH=$POWSYBL_METRIX_HOME/bin:$PATH
+```
+
+On Windows, follow for example [this guide](https://www.architectryan.com/2018/03/17/add-to-the-path-on-windows-10/).
+
+To check if it works, open a new terminal and type the `itools` command. You should see
+the following answer:
+
+```
+$ itools
+usage: itools [OPTIONS] COMMAND [ARGS]
+
+Available options are:
+    --config-name <CONFIG_NAME>   Override configuration file name
+
+Available commands are:
+
+Computation:
+    loadflow                                 Run loadflow
+
+Data conversion:
+    convert-network                          convert a network from one format to another
+
+Metrix:
+    mapping                                  Time series to network mapping tool
+    metrix                                   Run Metrix
+    metrix-die                               Generate Metrix DIE files
+
+Misc:
+    generate-completion-script               Generates a bash autocompletion script
+    plugins-info                             List the available plugins
+
+Script:
+    run-script                               run script (only groovy is supported)
+```
+
+*Note: If you already have another version of itools installed (for example if you use powsybl-dependency),
+you may want to have another configuration to use a specific command so that you can
+use both independently:*
+
+```shell
+alias itoolsmetrix='<repository_where_you_unzipped_itools-metrix>/bin/itools'
+```
+
+#### Metrix configuration
+
+Now you need to add some configuration to your PowSyBl `config.yml` file. By default,
+this file should be in the `<USER_HOME>/.itools` directory. Create the file if it does not already exist.
+Then add the following lines:
+
+```yml
+metrix:
+  home-dir: <directory_where_you_unzipped_metrix-simulator> # required
+  command: metrix-simulator
+
+  iidm-export-version: "1.11" # default to latest available version
+  constant-loss-factor: false # enable constant loss factor
+  chunk-size: 10 # size of the batch processed by Metrix
+  result-limit: 10000 # max allowed output count
+  debug: false # enable debug mode
+  log-level: 2 # Metrix log level, available values: 0 (trace), 1 (debug), 2 (info), 3 (warn), 4 (error), 5 (critical)
+  debug-log-level: 0 # Metrix log level when debug mode is enabled, available values: 0 (trace), 1 (debug), 2 (info), 3 (warn), 4 (error), 5 (critical)
+
+mapping-default-parameters:
+  tolerance-threshold: 0.0001f
+
+metrix-default-parameters:
+  computation-type: LF # default computation type
+  loss-factor: 0f # default loss factor value
+  nominal-u: 100 # default nominal U
+```
+
+
+
 ```{toctree}
 ---
 maxdepth: 2