The example in rsf/tutorials/hilbert reproduces the tutorial from Steve Purves on phase and the Hilbert transform. The tutorial was published in the October 2014 issue of The Leading Edge. 
Madagascar users are encouraged to try improving the results.
See also:
March 26, 2015 Documentation No comments
Another old paper is added to the collection of reproducible documents:
When is anti-aliasing needed in Kirchhoff migration?
We present criteria to determine when numerical integration of seismic data will incur operator aliasing. Although there are many ways to handle operator aliasing, they add expense to the computational task. This is especially true in three dimensions. A two-dimensional Kirchhoff migration example illustrates that the image zone of interest may not always require anti-aliasing and that considerable cost may be spared by not incorporating it.