{
  "name": "perimeter",
  "type": "function",
  "groups": ["GeometryGroup"],
  "description": "Returns the perimeter of a geometry polygon object. Calculations are always planimetric in the Spatial Reference System (SRS) of this geometry, and the units of the returned perimeter will match the units for the SRS. This differs from the calculations performed by the $perimeter function, which will perform ellipsoidal calculations based on the project's ellipsoid and distance unit settings.",
  "arguments": [{
    "arg": "geometry",
    "description": "polygon geometry object"
  }],
  "examples": [{
    "expression": "perimeter(geom_from_wkt('POLYGON((0 0, 4 0, 4 2, 0 2, 0 0))'))",
    "returns": "12.0"
  }],
  "tags": ["planimetric", "distance", "polygon", "perimeter", "spatial", "reference", "system", "calculations", "project", "differs", "object", "match", "settings", "ellipsoid", "units"]
}