*Richard McDonnell*richard.mcdonnell at opw.ie
<mailto:qgis-user%40lists.osgeo.org?Subject=Re%3A%20%5BQgis-user%5D%20Problem%20Noticed%20with%20QGIS&In-Reply-To=%3C9708d6dac99943929281a173e54a9e6f%40opw.ie%3E>
/Tue Nov 29 07:17:48 PST 2022/
------------------------------------------------------------------------
1. If I use the option [Create temporary Layer] it produces a Singlepart
Geometry as Expected, If I save the output to a File, the resultant geometry is
stated as Polygon (MultiPolygon) Its the same for Linestrings also.
Hi Richard,
as explained (also by me) in the linked issue report [1], the line
(PolyLine) and polygon (Polygon) ESRI Shapefile layer types are actually
multi-part layer types which can store both multi-part geometries with
only one part and multi-part geometries with more than one part.
Only the point layer type has two different ESRI Shapefile layer types:
the ESRI Shapefile Point type (which is a single-part type and can store
only single-part geometries) and the ESRI Shapefile MultiPoint type
(which is a multi-part type and can store multi-part geometries both
with only one part and with more than one part).
Please see the ESRI Shapefile Technical Description [2].
If you want to check that a line (PolyLine) and polygon (Polygon) ESRI
Shapefile layer imported in QGIS contains features with only 1 part, you
need to check the number of part for each feature, for example using the
num_geometries function [3] in the field calculator.
Best regards.
Andrea Giudiceandrea
[1] https://github.com/qgis/QGIS/issues/50720
[2] https://www.esri.com/Library/Whitepapers/Pdfs/Shapefile.pdf/
[3]
https://docs.qgis.org/3.22/en/docs/user_manual/expressions/functions_list.html#num-geometries
_______________________________________________
Qgis-user mailing list
[email protected]
List info: https://lists.osgeo.org/mailman/listinfo/qgis-user
Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
