It's Groovy Week: Aggregate MultiLineStrings
This is the third time to get "Groovy" this week! Today, we will look into how we can simplify Multi-Geometries to simple geometries using a specific script. This is often necessary when the target data model only allows simple geometries, but we can actually have composite and multi-geometries (
MultiPolygon) in the source data.
Like the previous posts, note that this article assumes you have working knowledge of hale»studio and know the terminology.
Wednesday's Script: Create LineStrings from MultiLineStrings (Johanna)
This Groovy Script was developed to aggregate MultiLineString geometries and convert them to LineStrings.
Background: This script was developed to process the 2018 HY-P Swisstopo data. A merge on the feature type level necessitated the use of aggregation to obtain one LineString per feature. The script below was used in a Greedy Groovy script function on the geometry property.
This script also contains a lot of great logging examples!
This is the full script:
You can download this script here and import it in hale»studio as a Groovy snippet by going to File -> Import -> Groovy Snippet. It assumes a certain geometry attribute name (
the_geom) that you might have to change.