join_attributes_by_location.py.md

Join attributes by location

Join attributes from a location layer to matching/non-matching location of a shape layer

Requirements & Installation

See README.md

Usage

Arguments

Argument	Summary	Description	Optional	Default	Type
-h/--help	display help	display detailed usage and examples	✔
--layer	join layer file path (absolute)	layer to join input attributes with (format gpkg, geojson, kml, shp)			string
--layername	join layer name	join layer name used in the output file name			string
--layerfields	join layer fields	join layer fields (space separated) to join append to input file (e.g.: 'fid name')			string
--indir	input directory (absolute)	input data directory path			string
--inpat	input files pattern	input data files pattern to process several files			string
--indel	input data delimiter	input data file delimiter	✔	,	string
--inxfield	input X field column	input data X field column (longitude)			string
		column name when headers present (lng) or 'field_#' (field_3)
--inyfield	input Y field column	input data Y field column (latitude)			string
		column name when headers present (lat) or 'field_#' (field_2)
--incrs	input CRS	input data CRS	✔	4326	integer
--innoheaders	input has no headers	input data files have no headers	✔
--outdir	output directory (absolute)	output data directory path			string
--jointype	join type	type of the final joined layer:	✔	1	integer
		0 - Create separate feature for each matching feature (one-to-many)
		1 - Take attributes of the first matching feature only (one-to-one)
--nonmatching	non matching	output non matching only	✔
--geopredicate	geometric predicate	geometric predicate criteria (space separated):	✔	5	integer
		0 - intersect
		1 - contain
		2 - equal
		3 - touch
		4 - overlap
		5 - within (similar to 0 but seems faster)
		6 - cross

Examples

See tests.tar.gz for sample files to run tests on

Join no-header location with highways appending attribute fid

python3 join_attributes_by_location.py \
    --layer $PWD/../tests/highways-buffered.gpkg \
    --layername highways-no-headers \
    --layerfields fid \
    --indir $PWD/../tests \
    --inpat test.no-headers.csv \
    --indel , \
    --inxfield field_2 \
    --inyfield field_1 \
    --incrs 4326 \
    --innoheaders \
    --outdir $PWD/../tests \
    --jointype 1 \
    --geopredicate 0

Same example with headers using default values

python3 join_attributes_by_location.py \
    --layer $PWD/../tests/highways-buffered.geojson \
    --layername highways-headers \
    --layerfields fid \
    --indir $PWD/../tests \
    --inpat test.headers.csv \
    --inxfield lng \
    --inyfield lat \
    --outdir $PWD/../tests

Output

Write matching or non-matching lines to a csv file under the output directory named after the input file with a suffix based on the layer name

Using input file tests.csv and layer name highways

• matching: tests.highways.csv
• non-matching: tests.highways.non-matching.csv

Documentation

https://docs.qgis.org/3.10/en/docs/user_manual/processing_algs/qgis/vectorgeneral.html#join-attributes-by-location

TODOs

• allow multiple join layers
• parallelization??