linux_dependencies_install.md

 # Installing dependencies on Linux #
 
 Here you will find the list of mandatory packages necessary to build the software on different Linux distribution.
-The building has been tested on the following Linux distributions:
+The building has been recently tested on the following Linux distributions:
 
 * [Ubuntu/Debian](#ubuntu)
+* [ArchLinux](#archlinux)
+
+The following have not been tested for a long time and are kept for reference:
 * [OpenSuze](#opensuze)
 * [CentOs](#centos)
 
@@ -17,11 +20,11 @@ Since this page is updated only once in a while, so you may encounter some probl
 
 ## Installing  ##
 
-### <a name=ubuntu>Ubuntu 18.04</a> ###
+### <a name=ubuntu>Ubuntu 20.04</a> ###
 
 To compile:
 ```shell
-sudo apt-get install cmake gcc g++ gfortran liblapack-dev swig python3-dev python3-numpy
+sudo apt-get install cmake gcc g++ gfortran liblapack-dev swig python3-dev python3-numpy python-is-python3
 ```
 Optional:
 ```shell
@@ -43,8 +46,17 @@ To read tutorials
 ```shell
 sudo apt-get install jupyter-notebook
 ```
-Everything should work for ubuntu 16 too except that `python3-vtk6` should be used and that hdf5
-is not available from the package manager and must be compiled from sources instead.
+For ubuntu 18, everything should work the same way except that `python-is-python3` is not available and each time the `python` command is run, then it should be replace by `python3`.
+For ubuntu 16 is the same as 18 except that `python3-vtk6` should be used and that hdf5 is not available from the package manager and must be compiled from sources instead.
+
+### <a name=archlinux> ArchLinux</a> ###
+
+The necessary recommended packages needed to build and use LMGC90 are:
+```shell
+sudo pacman -S gcc-fortran make cmake swig python
+sudo pacman -S python-numpy python-scipy python-matplotlib python-h5py
+sudo pacman -S vtk glew openmpi netcdf proj gdal pugixml libtheora ffmpeg unixodbc pdal qt5-base
+```
 
 ### <a name=opensuze> OpenSuse Leap 42.1 </a> ###