Fix sign consistency in Newton method 2D code#157
Open
Chessing234 wants to merge 1 commit intomitmath:Fall24from
Open
Fix sign consistency in Newton method 2D code#157Chessing234 wants to merge 1 commit intomitmath:Fall24from
Chessing234 wants to merge 1 commit intomitmath:Fall24from
Conversation
The LaTeX defines δ = J⁻¹·(-T(x₀)) and x₁ = x₀ + δ, but the code had δ = J⁻¹·T(x₀) and x₁ = x₀ - δ. The signs cancel so the result was correct, but the code was inconsistent with the equations shown to students. Now the code matches the math. Fixes mitmath#112 Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Fixes #112
The Julia code for Newton's method in 2D (
newton2D_step) usedδ = J \ T(x)andreturn x - δ, while the LaTeX equations defineJ · δ = -T(x₀)andx₁ = x₀ + δ. The signs cancel so the computation was correct, but the mismatch is confusing for students.Changed the code to match the equations:
δ = J \ -T(x)(wasJ \ T(x))return x + δ(wasx - δ)