{
  "name": "y_at",
  "type": "function",
  "groups": ["GeometryGroup"],
  "description": "Retrieves a y coordinate of the geometry.",
  "arguments": [{
    "arg": "geometry",
    "description": "geometry object"
  }, {
    "arg": "vertex",
    "description": "index of the vertex of the geometry (indices start at 0; negative values apply from the last index, starting at -1)"
  }],
  "examples": [{
    "expression": "y_at( geom_from_wkt( 'POINT(4 5)' ), 0 )",
    "returns": "5"
  }],
  "tags": ["retrieves", "coordinate"]
}