sympy__sympy-14817

Based on the issue description, error traceback, and hints, I can understand the problem and create a fix. The issue is:

Skills
AI research
1

What it does and how to use it

A skill that teaches Claude Code to do ai research tasks well. It is packaged knowledge the model uses whenever it is relevant.

Install the skill (command above).
In Claude Code, describe what you need - the skill turns on by itself when the context fits.
No commands to memorize: you talk in plain language and the skill does the rest.

Install (Claude Code)

mkdir -p .claude/skills/sympy-sympy-14817 && curl -fsSL https://doutorai.pt/data/lib/skills__sympy-sympy-14817.md -o .claude/skills/sympy-sympy-14817/SKILL.md

Paste this command into the terminal, in your project folder, and the component installs automatically.

Content

Based on the issue description, error traceback, and hints, I can understand the problem and create a fix. The issue is:

1. In `_print_MatAdd`, the code uses `S(item.args[0]).is_negative` to check if an item is negative
2. `S()` is `sympify()` which tries to parse string arguments
3. When a MatrixSymbol has a name with special characters like `*`, sympify fails

The fix should use the same approach as `_print_Add` - checking if the coefficient is negative by looking at the actual SymPy object's properties rather than using sympify.

Looking at the error message and the hints:
- The problemati

- 🔒 Full content on the Pro plan (€7.99/month) -

Need help with Claude Code?

Ask Dr AI - it explains things simply.

Need a tailor-made solution?

Not sure where to start with AI in your business? Get a free assessment and a tailored plan - no commitment.

Save hours every week with AI, no hassle

Doutor AI gives you 1,859 ready-to-copy AI prompts, by industry and in plain English - plus a complete technical library for those who want to go further.

See plans