English
For DecidableEq m, (f : α → β) satisfies map (updateRow M i b) f = updateRow (M.map f) i (f ∘ b).
Русский
Для DecidableEq m: map (updateRow M i b) f = updateRow (M.map f) i (f ∘ b).
LaTeX
$$$ \mathrm{map}\ (\mathrm{updateRow}\ M\ i\ b)\ f = \mathrm{updateRow}\ (M.map f)\ i\ (f \circ b) $$$
Lean4
theorem map_updateRow [DecidableEq m] (f : α → β) : map (updateRow M i b) f = updateRow (M.map f) i (f ∘ b) :=
by
ext
rw [updateRow_apply, map_apply, map_apply, updateRow_apply]
exact apply_ite f _ _ _