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[Merged by Bors] - feat(Analysis/Analytic/Meromorphic): more API for meromorphic functions #9621
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bors d+
Thanks!
AnalyticAt.unique_eventuallyEq_zpow_smul_nonzero ⟨g, hg_an, hg_ne, hg_eq⟩⟩ | ||
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/-- Compatibility of notions of `order` for analytic and meromorphic functions. -/ | ||
lemma order_of_analyticAt {f : 𝕜 → E} {x : 𝕜} (hf : AnalyticAt 𝕜 f x) : |
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could you change the name of the lemma and move it into the AnalyticAt
namespace?
∃ (n : ℤ) (g : 𝕜 → E), AnalyticAt 𝕜 g x ∧ ∀ᶠ z in 𝓝[≠] x, f z = (z - x) ^ n • g z := by | ||
constructor | ||
· intro hf_m | ||
rcases eq_or_ne hf_m.order ⊤ with ho | ho |
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do you really need to use the order for this? You could just start from the definition of a meromorphic function, and multiply by (z - x) ^ (-n)
.
MeromorphicOn f U := | ||
fun x hx ↦ (hf x hx).meromorphicAt | ||
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lemma meromorphicOn_id {U : Set 𝕜} : MeromorphicOn id U := fun x _ ↦ meromorphicAt_id x |
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With the new dot notation in Lean 4, this kind of lemma should be named MeromorphicOn.id
. The reason is that, if you're proving that a function is MeromorphicOn
, then Lean 4 will let you use .id
for MeromorphicOn.id
, and it turns out to be really convenient. Same thing below for const
.
✌️ loefflerd can now approve this pull request. To approve and merge a pull request, simply reply with |
Many thanks @sgouezel for the review! bors r+ |
…ns (#9621) This PR adds "order of vanishing" for meromorphic functions, and some basic API for functions `MeromorphicOn` a set.
Build failed (retrying...): |
…ns (#9621) This PR adds "order of vanishing" for meromorphic functions, and some basic API for functions `MeromorphicOn` a set.
Pull request successfully merged into master. Build succeeded: |
…ns (#9621) This PR adds "order of vanishing" for meromorphic functions, and some basic API for functions `MeromorphicOn` a set.
This PR adds "order of vanishing" for meromorphic functions, and some basic API for functions
MeromorphicOn
a set.