The first step to using Octofitter.jl is to install Julia. If you're used to Python, don't worry –- Julia is easy to install, and you won't need to code anything other than changing your input data.
Visit the julialang.org Downloads page, and select the latest stable version for your operating system. This is 1.9.1 at the time of writing. Click the
[help] links next to your operating system if you require more detailed instructions.
- Start julia in a terminal by running
]to enter package-mode (see Julia documentation for more details)
add Octofitter Distributions Plots CairoMakie PairPlots
You will need the Distributions,jl package so that you can specify priors for different parameters in your models. Plots.jl is for visualizing your results and is optional. CairoMakie.jl and PairPlots.jl can be used for generating corner plots and are also optional.
Some Octofitter functionality exists in extension packages, including radial velocity fitting. If you need one of these packages you can install them like so:
pkg> add http://github.com/sefffal/Octofitter.jl:OctofitterImages pkg> add http://github.com/sefffal/Octofitter.jl:OctofitterRadialVelocity pkg> add http://github.com/sefffal/Octofitter.jl:OctofitterVisibilities
That is, specify the extension package you want to install after the colon (
These aren't included by default since they may include a number of heavier dependencies that aren't needed by all users. They are descibed further in relevant sections of the documentation.
Start with the Fit Relative Astrometry tutorial. It shows how one can model the orbit of one planet based on relative astrometry points.