QGIS/resources/function_help/json/pole_of_inaccessibility
Harrissou Sant-anna 97247efef4 Various improvements to expression
- Add/fix details to description and examples to illustrate
- indicate string for geom_to_wkt
2020-08-31 11:19:06 +10:00

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{
"name": "pole_of_inaccessibility",
"type": "function",
"groups": ["GeometryGroup"],
"description": "Calculates the approximate pole of inaccessibility for a surface, which is the most distant internal point from the boundary of the surface. This function uses the 'polylabel' algorithm (Vladimir Agafonkin, 2016), which is an iterative approach guaranteed to find the true pole of inaccessibility within a specified tolerance. More precise tolerances require more iterations and will take longer to calculate.",
"arguments": [ {"arg":"geometry","description":"a geometry"},
{"arg":"tolerance","description":"maximum distance between the returned point and the true pole location"}],
"examples": [ { "expression":"geom_to_wkt(pole_of_inaccessibility( geom_from_wkt('POLYGON((0 1, 0 9, 3 10, 3 3, 10 3, 10 1, 0 1))'), 0.1))'", "returns":"'Point(1.546875 2.546875)'"}]
}