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name: crs-transform description: "Guides Fiona CRS construction, inspection, coordinate transformation, geometry transformation, and PROJ-backed interoperability workflows." disable-model-invocation: true metadata: disco-role: operating license: BSD 3-Clause

Fiona CRS and transforms

Use this route when the task names EPSG/PROJ/WKT, needs to inspect collection CRS, transform coordinates or GeoJSON-like geometries, or combine Fiona with PyProj or Shapely. Read the API reference for verified signatures and workflows for patterns.

• Use vector-io for opening and writing datasets and copying profile metadata.
• Use environment-cloud when CRS operations fail because PROJ/GDAL data or compiled libraries are missing.
• Read integrations before crossing into Shapely or PyProj.
• Read troubleshooting for invalid CRS, axis/units, antimeridian, or precision issues.

Fiona transforms coordinates through GDAL/PROJ but does not perform general geometry analysis, topology repair, buffering, or spatial predicates.