create: `subspace_mlp_demo.py` (#647)
create: `subspace_mlp_demo.py` (#647)

* create: subspace_mlp_demo.py

* feat: subspace_mlp_demo.py

* fix: subspace_mlp_demo.py

* style: subspace_ml_demo.py

* feat: subspace_mlp_demo.py

Add test-set accuracy estimation for multiple d; clean code

* style: subspace_mlp_demo.py

Fix figure size

* refactor subspace_mlp_demo.py

rename theta_to_flat_params -> convert_params_from_subspace_to_full

* refactor: subspace_mlp_demo

rename normal_loss -> cross_entropy_loss fn

* refactor: subspace_mlp_demo

Rename variables; add documentation

* refactor: subspace_mlp_demo

rename variables

* refactor: subspace_mlp_demo

rename variables

* refactor: subspace_mlp_demo

rename input and ouput labels

* refactor subspace_mlp_demo

Derive n_features from dataset

* fix: subspace_mlp_demo

Add multiple subspaces to test
probml/pyprobml,probml/pyprobml,probml/pyprobml,probml/pyprobml