{ "name": "simplify_vw", "type": "function", "groups": ["GeometryGroup"], "description": "Simplifies a geometry by removing nodes using an area based threshold (ie, the Visvalingam-Whyatt algorithm). The algorithm removes vertices which create small areas in geometries, e.g., narrow spikes or nearly straight segments.", "arguments": [{ "arg": "geometry", "description": "a geometry" }, { "arg": "tolerance", "description": "a measure of the maximum area created by a node for the node to be removed" }], "examples": [{ "expression": "geom_to_wkt(simplify_vw(geometry:=geom_from_wkt('LineString(0 0, 5 0, 5.01 10, 5.02 0, 10 0)'),tolerance:=5))", "returns": "'LineString(0 0, 10 0)'" }], "tags": ["spikes", "areas", "straight", "nodes", "algorithm", "area", "simplifies", "removes", "narrow", "segments", "visvalingam", "threshold", "create", "vertices", "removing", "based", "small"] }