# GeoReduceGeometry - script and chart function

GeoReduceGeometry() is used to reduce the number of vertices of a geometry, and to aggregate a number of areas into one area, but still displaying the boundary lines from the individual areas.

Syntax:

GeoReduceGeometry(field\_name[, value])

Return data type: string

Arguments:

Arguments

| Argument | Description |
| --- | --- |
| field\_name | A field or expression referring to a field containing the geometry to be represented. This could be either a point (or set of points) giving longitude and latitude, or an area. |
| value | The amount of reduction to apply to the geometry. The range is from 0 to 1, with 0 representing no reduction and 1 representing maximal reduction of vertices.<br><br>Information noteUsing a value of 0.9 or higher with a complex data set can reduce the number of vertices to a level where the visual representation is inaccurate. |

GeoReduceGeometry() also performs a similar function to, GeoAggrGeometry() in that it aggregates a number of areas into one area. The difference being that individual boundary lines from the pre-aggregation data are displayed on the map if you use GeoReduceGeometry().

As GeoReduceGeometry() is an aggregating function, if you use it in the script a LOAD statement with a Group by clause is required.

[](https://help.qlik.com/en-US/sense/Subsystems/Hub/Content/Sense_Hub/Scripting/GeospatialFunctions/GeoReduceGeometry.htm)

#### Examples:

This example loads a KML file with area data, and then loads a table with the reduced and aggregated area data.

```
[MapSource]:
LOAD [world.Name],
	[world.Point],
	[world.Area]
 FROM [lib://Downloads/world.kml]
(kml, Table is [World.shp/Features]);

Map:
LOAD world.Name, 
     GeoReduceGeometry(world.Area,0.5) as [ReducedArea]
resident MapSource Group By world.Name;
```

```
 
```

```

Drop Table MapSource;
```

## Learn more

* [GeoAggrGeometry - script and chart function](https://help.qlik.com/en-US/sense/May2025/Subsystems/Hub/Content/Sense_Hub/Scripting/GeospatialFunctions/GeoAggrGeometry.htm)
* [Loading your own map data](https://help.qlik.com/en-US/sense/May2025/Subsystems/Hub/Content/Sense_Hub/Visualizations/Map/load-map-data.htm)