Commit 2022-11-12 22:46 f0f3d964
View on Github →feat(linear_algebra/{basic, affine_space/restrict}): better support for restriction of affine and linear maps (#16397)
- Generalizes
linear_map.restrict
to allow independent but simultaneous restriction of domain and codomain in a backwards compatible way (except for one type inference failure inalgebra.lie.of_associative
that had to be fixed manually). - Adds
linear_map.restrict'
as an alternative tolinear_map.restrict
that takes a proof that the image of the new domain must be contained in the new codomain. - Introduces
affine_map.restrict
for restriction of affine maps in a new file calledlinear_algebra/affine_space/restrict.lean
and lemmata about injectivity, surjectivity and the coercion of a restricted map. Design choice: A new filerestrict.lean
was created becauseaffine_subspace.lean
is already very long andaffine_map.lean
does not know about affine maps.