Caesar.jl is one of the packages within the JuliaRobotics community, and adheres to the code-of-conduct.

Local Dependencies

The following system packages are used by Caesar.jl:

# required packages
sudo apt-get install hdf5-tools imagemagick

# optional packages
sudo apt-get install graphviz

New to Julia and want a full Development Install

Local Installation of Julia

Although Julia (or JuliaPro) can be installed on a Linux computer using the apt package manager, we are striving for a fully local installation environment which is highly reproducible on a variety of platforms.

The easiest method is–-via the terminal–-to download the desired version of Julia as a binary, extract, setup a symbolic link, and run:

cd ~
mkdir -p .julia
cd .julia
wget https://julialang-s3.julialang.org/bin/linux/x64/1.3/julia-1.3.1-linux-x86_64.tar.gz
tar -xvf julia-1.3.1-linux-x86_64.tar.gz
rm julia-1.3.1-linux-x86_64.tar.gz
cd /usr/local/bin
sudo ln -s ~/.julia/julia-1.3.1/bin/julia julia

Feel free to modify this setup as you see fit.

This should allow any terminal or process on the computer to run the Julia REPL by type julia and testing with:

[Optional] Quick Test that Julia is Working

Run Julia in REPL (console) mode:

$ julia
julia> println("hello world")
"hello world"

Maybe a script, or command:

user@...$ echo "println(\"hello again\")" > myscript.jl
user@...$ julia myscript.jl
hello again
user@...$ rm myscript.jl

user@...$ julia -e "println(\"one more time.\")"
one more time.
user@...$ julia -e "println(\"...testing...\")"

When searching for Julia related help online, use the phrase 'julialang' instead of just 'julia'. For example, search for 'julialang workflow tips' or 'julialang performance tips'. Also, see FAQ - Why are first runs slow?, which is due to Just-In-Time/Pre compiling and caching.

Setup Juno IDE Environment

Juno IDE allows for interactive development of Julia code by extending the Atom text editor with a few packages. Download and install Atom as instructed on the website, or via command line:

mkdir -p ~/Downloads/atom
cd ~/Downloads/atom
wget https://atom.io/download/deb -q --show-progress
sudo dpkg -i deb

After installing and running Atom, you can choose to either install uber-juno package in one go or install the three associated packages individually. In Atom, open the command pallette by pressing Ctrl + Shft + p and typing settings. Go to the install tab, search for and install either


or the individual packages directly:


Some situations have required the user separately installing the Atom.jl Julia package via command line (if Juno does not automatically install Atom.jl for you). Atom.jl can then be installed with Julia's package manager and add Atom — see below.

There are a variety of useful packages in Atom, such as minimap and minimap-git. Julia packages are independent of the Atom packages and installed via the Julia Pkg Package.

Julia Packages

The philosophy around Julia packages are discussed at length in the Julia core documentation, where each Julia package relates to a git repository likely found on Github.com. To install a Julia package, simply open a julia REPL (equally the julia REPL in Atom/Juno) and type:

] # activate Pkg manager
(v1.3) pkg> add Caesar

These are registered packages maintained by JuliaRegistries/General. Unregistered latest packages can also be installed with using only the Pkg.develop function:

# Just using Caesar URL as an example --  Caesar is already on JuliaRegistries/General
using Pkg

Unless you change the default environment variable JULIA_PKG_DIR, all packages (git repos) are cloned/installed to ~/.julia. You can work with the packages as regular git repositories there.

Install Visualization Tools

RoMEPlotting.jl (2D) and Arena.jl (3D) as optional visualization packages:

(v1.2) pkg> add RoMEPlotting

# separately
(v1.2) pkg> add Arena#master

Arena.jl and Amphitheater.jl are currently being refactored as part of the broader DistributedFactorGraph migration, the features are are in beta stage (1Q2020).

Install Visualization Utils (e.g. Arena.jl)

3D Visualizations are provided by Arena.jl as well as development package Amphitheater.jl. Please follow instructions on the Visualizations page for a variety of 3D utilities.

Arena.jl can be installed with the following steps:

add Arena

of the latest development version:

(v1.0) pkg> add Arena#master

RoMEPlotting.jl for 2D plots

Previous versions of libraries required the following Linux system packages be installed:

sudo apt-get install libfontconfig1
sudo apt-get install gettext
sudo apt-get install libcairo2
sudo apt-get install libpango1.0-0  # or libpango1.0-1

As of 1Q2020 it is likely that most systems won’t require a system install of libpango or even libcairo.

Please install the latest RoMEPlotting using Package manager as follows:

$ julia
julia> ] # to get package manager
(v1.2) pkg> add RoMEPlotting

Alternatively, the dev command –- i.e. (v1.2) pkg> dev RoMEPlotting –- will clone the RoMEPlotting.jl git repository to your local .julia/dev/RoMEPlotting folder.

The "I Know Julia" Installation (TL;DR)

Install Inference Tools

Add Caesar to your Julia packages, you can install the metadata registered package 'Caesar' in Julia 1.0 with:

julia> ] # to enable package manager
(v1.0) pkg> add Caesar

Unit tests can further be performed for the upstream packages as follows – NOTE first time runs are slow since each new function call or package must first be precompiled.

# the multimodal incremental smoothing and mapping solver
(v1.2) pkg> test IncrementalInference
# robotics related variables and factors to work with IncrementalInference -- can be used standalone SLAM system
(v1.2) pkg> test RoME
# umbrella framework with interaction tools and more -- allows stand alone and server based solving
(v1.2) pkg> test Caesar

Ahead Of Time Compile RoME.so

In RoME, run the compileRoME/compileRoMESysimage.jl script

To use RoME with the newly created sysimage, start julia with:

julia -O3 -J ~/.julia/dev/RoME/compileRoME/RoMESysimage.so

Install "Just the ZMQ/ROS Runtime Solver" (Linux)

Work in progress (see issue #278).

Contributing, Issues, or Comments

Please feel free to open issues with Caesar.jl or even Fork and Pull Request as required. General conversations or comments can be made in the Caesar Gist.