From 3934e2d306bf4877255605fd72f47a40a6472889 Mon Sep 17 00:00:00 2001
From: Tom Henderson <tomh@tomh.org>
Date: Mon, 13 Mar 2023 08:43:28 -0700
Subject: [PATCH] doc: Add Eigen3 installation guidance

---
 doc/installation/source/linux.rst  | 2 ++
 doc/installation/source/macos.rst  | 2 ++
 doc/installation/source/system.rst | 6 ++++++
 3 files changed, 10 insertions(+)

diff --git a/doc/installation/source/linux.rst b/doc/installation/source/linux.rst
index 27ad5088a..0f1cf65a8 100644
--- a/doc/installation/source/linux.rst
+++ b/doc/installation/source/linux.rst
@@ -86,6 +86,8 @@ Please see below subsections for Python-related package requirements.
   |                             | ``texlive-extra-utils texlive-latex-extra``                |
   |                             | ``texlive-font-utils``                                     |
   +-----------------------------+------------------------------------------------------------+
+  | Eigen3                      | ``libeigen3-dev``                                          |
+  +-----------------------------+------------------------------------------------------------+
   | GNU Scientific Library      | ``gsl-bin libgsl-dev libgslcblas0``                        |
   +-----------------------------+------------------------------------------------------------+
   | XML config store            | ``libxml2 libxml2-dev``                                    |
diff --git a/doc/installation/source/macos.rst b/doc/installation/source/macos.rst
index aadf5fc17..918671b13 100644
--- a/doc/installation/source/macos.rst
+++ b/doc/installation/source/macos.rst
@@ -105,6 +105,8 @@ For MacPorts packages we show the most recent package version available as of ea
   |                             |                                  | ``pyXX-sphinx``, with    |
   |                             |                                  | `XX`` the Python version |
   +-----------------------------+----------------------------------+--------------------------+
+  | Eigen3                      | ``eigen``                        | ``eigen3``               |
+  +-----------------------------+----------------------------------+--------------------------+
   | GNU Scientific Library      | ``gsl``                          | ``gsl``                  |
   +-----------------------------+----------------------------------+--------------------------+
   | XML config store            | ``libxml2``                      | ``libxml2``              |
diff --git a/doc/installation/source/system.rst b/doc/installation/source/system.rst
index def660b16..a4c8731ba 100644
--- a/doc/installation/source/system.rst
+++ b/doc/installation/source/system.rst
@@ -183,6 +183,12 @@ The ns-3 manual (``doc/manual``), tutorial (``doc/tutorial``) and others are wri
 reStructuredText for Sphinx, and figures are typically in dia.  To build PDF versions,
 `texlive <https://www.tug.org/texlive/>`_ packages are needed.
 
+Eigen3 support
+==============
+`Eigen3 <https://gitlab.com/libeigen/eigen>`_ is used to support more efficient calculations
+when using the `3GPP propagation loss models <https://www.nsnam.org/docs//models/html/propagation.html#threegpppropagationlossmodel>`_
+in LTE and NR simulations.
+
 GNU Scientific Library (GSL)
 ============================