the competition's expm vs ours

[Jordi Gutiérrez Hermoso]

I just ran into a "benchmark" in a blog somewhere that suggests that
our expm is slower than Matlab's.

Can someone with Matlab access provide insight, please? Are they both
m-files or compiled or what? Are we using different algorithms?

I've always wanted to read up on the literature on how to implement
matrix expoonentials and those famous papers, so this looks like a
good excuse to do so.

- Jordi G. H.