josdejong/mathjs

math.rationalize() made some mistakes

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#2,080 opened on Jan 12, 2021

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 (5 comments) (0 reactions) (0 assignees)JavaScript (1,314 forks)batch import
featurehelp wanted

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Description

So I'm extremely happy with math.js, but I've had some problems with the following. Does anyone have a fix, I'm not sure what to do.

(a - b) + (a + 2b) was solved as a - b + a + 2 b and it should be 2a + b

2y + (3 - 4x) * 2 - 7x was solved as 2 y - 8 * x - 7 * x + 6 and it should be -15x + 2y + 6

2y + (3 + 4x) * 3 - 8x was solved as 2 y - 8 * x + 9 + 12 * x and it should be 4x + 2y + 9

Contributor guide

Research direction
Look at the rationalize function implementation and write test cases to reproduce the incorrect simplifications. Check how operator precedence and parentheses are handled.
Tech stack
javascript
Domain
backend
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
JavaScriptBasic algebra
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
65