24.1.6. Fix Geometry

24.1.6.1. Delete small angles 

Deletes vertices based on an error layer from the Small angles algorithm. When deletion of a vertex results in a duplicate vertex (when a spike vertex is deleted), the duplicate vertex is deleted to keep a single vertex and preserve topology.

Attention

This algorithm removes the vertex at the reported small angles, generating new segments that may form a new small angle.

../../../../_images/fix_geometry_angle.png — Fig. 24.3 Fixing reported errors on a line feature for angles lower than 15°.

Parameters

Basic parameters

Label	Name	Type	Description
Input layer	`INPUT`	[vector: line, polygon]	Layer with the geometries to fix, same as input in the check algorithm
Error layer	`ERRORS`	[vector: point]	Point layer with the errors location, generated by the check algorithm
Field of original feature unique identifier	`UNIQUE_ID`	[tablefield: any]	Field storing unique values for feature identification in input layer, as set in the check algorithm
Field of part index	`PART_IDX`	[tablefield: integer] Default: `gc_partidx`	Field storing the erroneous feature’s geometry part number.
Field of ring index	`RING_IDX`	[tablefield: integer] Default: `gc_ringidx`	Field storing the erroneous feature’s geometry ring number.
Field of vertex index	`VERTEX_IDX`	[tablefield: integer] Default: `gc_vertidx`	Field storing the erroneous feature’s geometry vertex number.
Small angle fixed layer	`OUTPUT`	[vector: same as input] Default: `[Create temporary layer]`	Specification of the output layer containing fixed features. One of: Create Temporary Layer (`TEMPORARY_OUTPUT`) Save to File… Save to Geopackage… Save to Database Table… The file encoding can also be changed here.
Report layer from fixing small angles	`REPORT`	[vector: point] Default: `[Create temporary layer]`	Specification of the output layer containing the fixes location. One of: Create Temporary Layer (`TEMPORARY_OUTPUT`) Save to File… Save to Geopackage… Save to Database Table… The file encoding can also be changed here.

Advanced parameters

Label

Name

Type

Description

Tolerance

TOLERANCE

[numeric: integer]

Default: 8

Numerical precision of geometric operations, given as an integer n, meaning that two vertices less than 10^-n apart (in map units) are considered to be merged.

Outputs

Label	Name	Type	Description
Report layer from fixing small angles	`REPORT`	[vector: point]	Output point layer representing the error locations and fix applied (the ID and name of the input layer, the ID, geometry part, ring and vertex index of the erroneous feature, x and y coordinates and value of the erroneous angle, the applied fix and its successfulness).
Small angle fixed layer	`OUTPUT`	[same as input]	Output layer with the geometry fix applied to the input features

Python code

Algorithm ID: native:fixgeometryangle

import processing
processing.run("algorithm_id", {parameter_dictionary})

The algorithm id is displayed when you hover over the algorithm in the Processing Toolbox. The parameter dictionary provides the parameter NAMEs and values. See Using processing algorithms from the console for details on how to run processing algorithms from the Python console.