QGIS Plugin: Nearest with greater value

Plugin for QGIS to get name (or ID) of and distance to the nearest feature with greater value in a certain field of a points layer. Returns points layer with added attributes and a line layer with connecting lines.

QGIS Plugin Registry: https://plugins.qgis.org/plugins/qgis_nearest_greater/
Source Code: Repository on Github
Bug tracker: https://github.com/florianneukirchen/qgis_nearest_greater/issues
License: GPL v2

Screenshot of the Plugin, with the result in the background (color of arrows: neargtdelta, labels: neargtcount)

About

Get name (or ID) of and distance to the nearest neighbour with greater value in a certain field. Input is a points layer. The main output is a points layer with added attributes neargtdist (distance), neargtdelta (difference of values), neargtname (name or ID) and neargtcount. The field neargtcount gives the count of incoming connecting lines linking to points with smaller value. Also returns a lines layer with connecting lines, as well as basic statistics of the distances and deltas (min, max, mean, quartiles).

Use cases

Install

Works with QGIS >= 3.18 (because it requires pyproj >= 3.0.0). You can install the plugin with the Plugin Manager in QGIS. Or clone / copy the source code into your QGIS plugin folder.

Changelog

1.1 (2023-1)

  • Set required QGIS version to >= 3.18 (because it requires pyproj >= 3.0.0)

1.0 (2022-10)

  • Add additional output field neargtdelta with the diffence of both values
  • Calculate statistics for delta
  • Improve strings in the UI

0.3 (2022-09)

  • Fix a bug by changing the names of added fields to neargtdist, neargtname, neargtcount. Don’t use underscore. Before, they were renamed by QGSIS when the layer was saved to a shapefile.

0.2 (2022-09)

  • Return additional field ‘nearest_gt_count’ with a count of the incoming links (i.e. connecting lines from points with smaller value)
  • Better handling of the distance value for the feature with greatest value. Three options: “NULL”, “1 Mio.”, “max distance + 1”.
  • Warn if the selected name field contains NULL or non-unique values
  • Add short help string

0.1 (2022-09)

Initial release