qgis-errors-projections
Installation
SKILL.md
qgis-errors-projections
Quick Reference
CRS Error Decision Table
| Symptom | Likely Cause | Jump To |
|---|---|---|
| Layer appears in wrong continent/ocean | Wrong EPSG code assigned | ERR-001 |
| Layer offset by ~100-200 meters | Missing datum transformation | ERR-003 |
| Layer appears stretched/squashed | Geographic CRS used for projected operations | ERR-001 |
| Coordinates swapped (X/Y flipped) | lat/lon vs lon/lat confusion | ERR-002 |
| Layer invisible (but valid) | CRS mismatch hidden by OTF reprojection | ERR-004 |
| Geometry operations return wrong values | Silent CRS corruption from wrong assignment | ERR-005 |
| Transform produces NaN or inf | QgsCoordinateTransform without context | ERR-006 |
| All CRS operations fail in standalone script | Missing srs.db (prefix path not set) | ERR-007 |