Advertisements I’m trying to prove in Lean 4 that for the naturals: q + q ^ 2 ≠ 7 So far, I have this proof: example : q + q ^ 2 ≠ 7 := by intro h have q00 : q = 0 ∨ 0 < q := by exact Nat.eq_zero_or_pos q cases q00… Read More Prove by matching specific natural numbers in Lean
Advertisements I can’t find any information online about the simp! tactic, although it is suggested by the autocomplete function on VSCode. I’ve tried using it and it seems to work differently from simp, but while I can trace the definition of simp back to its source file, this doesn’t seem possible for simp!. Is this… Read More what's the difference between `simp` and `simp!`? Where is `simp!` defined?
Advertisements In the following, the rewrite fails because it "did not find instance of the pattern in the target expression": example (l1:List Nat)(l2:List Nat)(n:Nat)(r:l1.length >= n)(p:l1.length = l2.length+1) : l2.length >= (n-1) := by rw [Nat.sub_le_iff_le_add] I’m confused why it doesn’t bind given that the goal seems to be a perfect fit. (note: this is… Read More Why Does Rewrite Fail to Bind?
Advertisements How to Build a Relevant Auto Generating Tags Recommendation Model in Python One of the most important features of any blog or website is its ability to recommend relevant tags to users. This not only helps users find related content easily, but it also improves the overall user experience. In this blog post, we’ll… Read More How to build relevant auto generating tags recommendation model in python
Advertisements I was making a new path for pages on my site and was trying to figure out how to path to my stylesheet and images cleanly. Here’s an element that shows my problem: <link rel="stylesheet" href="/src/styles.css"> My local copy of my site is hosted here at "E:/Documents/WEBSITE", the local page I’m trying to link… Read More relative src and href paths work live but not local
Advertisements I want to prove the fact "A function is injective, then it has left-inverse." in Lean Prover. As you know, in standard proof of this theorem, ( https://math.stackexchange.com/questions/2099699/left-inverse-in-f-a-iff-injective-proof ), we should define a function which is defined by case-by-case form. But I think that there is no way to define case-by-case form function in… Read More How can I define a function in Lean prover? (In "A function is injective then has left inverse")