Commit 2023-12-22 10:33 98067b25
View on Github →feat(LinearAlgebra/Dimension): add various surjective_injective
results (#9156)
Add various results concerning modules M / R
and M' / R'
with maps i : R -> R'
and j : M -> M'
which are compatible with scalar multiplications on M
and M'
.
- if
i : R' -> R
is injective andj
is injective, then:LinearIndependent.map_of_injective_injective
:j
preserves linear independent subsets.[lift_]rank_le_of_injective_injective
: rank ofM / R
is smaller than or equal to the rank ofM' / R'
.
- if
i
is surjective andj
is injective, then:LinearIndependent.map_of_surjective_injective
:j
preserves linear independent subsets.[lift_]rank_le_of_surjective_injective
: rank ofM / R
is smaller than or equal to the rank ofM' / R'
.
- if
i
andj
are both bijective, then[lift_]rank_eq_of_equiv_equiv
: rank ofM / R
is equal to the rank ofM' / R'
. Also add theAlgebra
versions of these results.