This is matlab implementation of some function
from python package [Strawberry Fields](https://strawberryfields.ai/)

They are handy for quantum optics mode calculations.

Them most notable functions are

- williamson: Williamson decomposition
- bloch_messiah: Bloch Messiah decomposition
- xpxp_to_xxpp: reordering covariance matrix
- xxpp_to_xpxp: reordering covariance matrix

There are also supporting functions:

- takagi: Takagi decomposition
- polardecomp: polar decomposition
- sympmat: creates symplectic form matrix


The initial conversion was done with Perplexity AI on 2024/11/19, but
it required a human intervention for some of the code.