# numpy.linalg.LinAlgError: Singular matrix

- **ID:** `python/numpy-linalg-singular`
- **Domain:** python
- **Category:** runtime_error
- **Verification:** ai_generated
- **Fix Rate:** 80%

## Root Cause

Matrix is not invertible (determinant zero); linear system has no unique solution.

## Version Compatibility

| Version | Status | Introduced | Deprecated |
|---------|--------|------------|------------|
| 3.x | active | — | — |

## Workarounds

1. **** (95% success)
   ```
   x = np.linalg.lstsq(A, b, rcond=None)[0]
   ```
2. **** (90% success)
   ```
   x = np.linalg.pinv(A) @ b
   ```

## Dead Ends

- **** — Perturbation may still be singular; unstable results (80% fail)
- **** — Ill-conditioned; large numerical error (70% fail)