Computing the bicharacter of diagonal harmonic polynomials

The main goal of this project is to compute the character of diagonal harmonic polynomials on $k$ rows of $n$ variables w.r.t. the action of $GL_k$ and $S_n$. See DiagonalCharacter.ipynb for explanations, as well as those slides of a talk on the topic (slow to start, but then you can play with the examples live!).

Dependencies: the SageMath open source mathematical system

License: GPL

## Subspace computation facilities

The code for this project includes generic facilities for computing subspaces of general Sage vector spaces like polynomial rings. See utilities.pyx, matrix_of_vectors.py, subspace.py.

This code is being extracted and refactored as a dedicated Sage package, to be eventually integrated into Sage:

https://github.com/darijgr/sage-subspace/

Don't edit the corresponding files in this repo; it will soon go away in favor of using sage-subspace.