This project consists of a single Sage Notebook with functions for computing the Waldspurger Transform of permutations and alternating sign matrices.
It also has code for computing David Anderson's essential set of signed permutations.
Among other things, this allows one to compute the base for type B.
waldspurgerTransform(Permutation([1,4,3,2])
returns the matrix:
[[0,0,0], [0,1,1], [0,1,1]]
To run this code, you'll need to have SageMath installed. Alternatively, you can run it in the cocalc cloud.