Read this first: https://doc.dhpc.tudelft.nl/delftblue/crash-course/
Then read this: https://m3g.github.io/JuliaNotes.jl/stable/instability/
The original Julia code is published in section 5.4 of 'Julia: A Fresh Approach to Numerical Computing', Jeff Bezanson, Alan Edelman, Stefan Karpinski and Viral B.Shah, SIAM REVIEW Vol. 59, No. 1 (2017), pp. 65–98, DOI: 10.1137/141000671, and reused by kind permission of SIAM.
Additional material is supplied under an MIT license.