Make valid

Draft: written, not yet checked by a person Operation · make-valid

Repairs invalid geometries, such as self-intersecting polygons, so later operations give correct results.

Pitfall. A repair can change a feature's geometry type (a polygon becoming a multipolygon or a collection); check the output types.

Pitfall. Engines repair the same shape differently, so results are not always identical across engines.

About this operation
Also called	Repair Geometry, Fix geometries, MakeValid, ST_MakeValid
Group	`vector/geometry`
Checks	`geometry.valid, geometry.repaired`
Pitfalls	2 listed above
Columbus tool	`vector_op · make_valid`
Notes	Not stated
Status	active
Broader	Not stated
Narrower	Not stated
Related	Not stated

Parameters

Not stated

Direction	Name	Type	Geometry	Note
Input	`layer`	vector	Not stated	Not stated
Output	`output`	vector	Not stated	Not stated

Engine	Tool	Parameters	Differences
`apache-sedona`	`sedona.sql.ST_MakeValid`	`layer` → `geometry`	A Spark SQL function: arguments are columns or column names, run over a Spark DataFrame.
`gdal`	`gdal vector make-valid`	`layer` → `input` `output` → `output`	None noted
`geopandas`	`geopandas.GeoSeries.make_valid`	Not stated	None noted
`postgis`	`st_makevalid`	`layer` → `#1`	The repair method is chosen in the params text ('method=structure'); the default is linework.
`qgis`	`native:fixgeometries`	`layer` → `INPUT` `output` → `OUTPUT`	Defaults to the structure method; GDAL, Shapely and PostGIS default to linework, which can give different shapes.
`sf`	`sf::st_make_valid`	`layer` → `x`	None noted
`shapely`	`shapely.make_valid`	`layer` → `geometry`	None noted
`terra`	`terra::makeValid`	`layer` → `x`	None noted