RooFitLite.jl

RooFitLite.jl is a small RooFit-style modeling layer for Julia HEP analyses. It represents observables, parameters, PDFs, generated data, fit results, and plots as separate Julia objects, following the same compositional idea used by ROOT RooFit while staying close to ordinary Julia package workflows.

The core workflow is:

1. Define one or more RealVar observables and parameters.
2. Build a PDF such as Gaussian, Exponential, or ArgusPdf.
3. Generate toy data with generate, or pass your own data.
4. Fit with fitTo when the Minuit2 extension is loaded.
5. Inspect or plot the model and fit result.

using RooFitLite
using Random: seed!

seed!(12345)

x = RealVar(:x, 0.0, limits=(0.0, 10.0))
mean = RealVar(:mean, 3.0, limits=(0.0, 5.0))
sigma = RealVar(:sigma, 0.8, limits=(0.1, 3.0))

model = Gaussian(:signal, x, mean, sigma)
data = generate(model, 100)

length(data.data)

100

See the tutorials for a fuller walk through of the RooFit-like pieces and a signal-plus-background model.