Non-Euclidean / non-vector space examples

[matbesancon]

Add examples and check adaptability of the code base to non-trivial atoms.

Easy ones:

• matrix spaces (symmetric or not)
• complex fields

More exotic:

• Base learners (i.e. https://arxiv.org/abs/1910.03742 Greedy Convex Ensemble)
• Measure spaces - (speculation) applications to optimal transport, Wasserstein barycenter problems

[matbesancon]

@alejandro-carderera that's the paper we mentioned in the call

[pokutta]

you mean the barron space one?

F. Bach: Breaking the Curse of Dimensionality with Convex Neural Networks: link

see page 9ff

[matbesancon]

The Greedy Convex Ensemble from above

[matbesancon]

done with KernelHerding