Questions tagged [rule-based]

The tag has no usage guidance.

23 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
5
votes
1answer
152 views

Nested rules in QGIS 2.18

I work with QGIS 2.18. I have a polygon shapefile with two atrributes: id (unique for each polygon) and type. I visualize the shapefile using the "type" attribute, but I would like to add a nested ...
4
votes
0answers
147 views

QGIS rule based symbology for rasters in Atlas?

I'm making species distribution maps and have got the Atlas working perfectly using a polygon layer to show the quarter degree grid cells for species observation records. I have ~ 250 species. Problem ...
3
votes
0answers
38 views

Arranging rulebased symbology alphabeticaly

QGIS version 3.16.4 I'm working with a layer that has a lot of different items in rulebased symbology. But they seem to be ordered randomly. Is it possible to arrange them alphabeticaly? I'm hoping ...
3
votes
0answers
21 views

How to prevent not visible objects (scale rules) from being identified?

In Symbology tab I am using rule-based symbols and I have defined visibility rules dependent on the minimum scale. Above some scale threshold some features are not visible as I expected. But when I am ...
3
votes
0answers
69 views

Moving individual labels & rule-based labelling in QGIS

I have been playing around with labels and came to a problem. Hopefully someone can pinpoint whether I'm doing something wrong or there is a systemic hurdle in Qgis. Are you allowed to move labels ...
3
votes
0answers
73 views

SOL help in QGIS: rule based styling to show timestamp increase via gradient

I have some polygon data from a tractor that shows it's route among other things. It has a timestamp column which I'd like to use to show the route in which the tractor drove through the field via a ...
2
votes
0answers
98 views

Projecting GeoTIFF onto shaped roofs using CGA rules

I am working with CityEngine 2019.1 and would like to project a GeoTIFF as a texutre onto shaped roofs of 3D-buildings. Currently I am trying with the following code which essentials are described on ...
2
votes
0answers
44 views

Save QGIS style created with espression string builder

I created a rule-based renderer with espression string builder, where I also use the function editor in Python. When I share the style (qml) file with others, I realized that the Python function I ...
2
votes
3answers
817 views

Multiple overriding rules for styling in QGIS 3.4.0

I am a total beginner to QGIS and still struggling with the basics. After a quick research on this forum I could not find the answer to my current issue. What I am trying to do is to colour the ...
2
votes
0answers
189 views

Set a rule for grow region in eCognition

I am using the grow region algorithm in eCognition sofrware in order to merge my candidate class. I want to set the rule : two candidated objects are merged only if the length/width ratio of the ...
1
vote
0answers
20 views

Action on filtered objects QGIS

I have got a point layer with about 1000 points. These point has a rule based symbology. So far so common. In this layer I have also some actions implemented. If I unselect some rules, that only the ...
1
vote
0answers
65 views

Using 1:n table relationships in rule-based symbology

I would like to use the value of a field/attribute in a parent table as a filter in an expression used to display features in the child table. Specifically, I have a 1:n relationship in my project: ...
1
vote
0answers
40 views

Labeling rule depending on whether label fits in polygon

I'm labeling some country polygons with their names. The data have one attribute with the full country name and another one with a short version (e.g. Sweden/SE). I want to label the countries with ...
1
vote
0answers
63 views

How to add rules to the topology from a .rul in ArcPy

I am trying to create a new topology using and ArcPy script and I have a lot of rules inside a .rul archive. The function to do that is: arcpy.AddRuleToTopology_management(out_topo, rule_type, in_fc1,...
1
vote
0answers
279 views

Rule-Based Styling not working in QGIS?

I'm trying to create a shapefile I can use as a template for a breeding bird survey. The basic gist was that each species has a two letter code and a colour depending on the BTO listing. Each bird is ...
1
vote
0answers
285 views

Automatic refreshing of Styles and legends in QGIS?

I am a new QGIS user. I come from an Arcgis background, but in my current work for a public administration I must use QGIS for interoperability. As an ArcMap user, I am used to certain "comforts", ...
1
vote
0answers
50 views

QGIS .shp joined to xlsx.vrt; Classify works, Rule-based does not

Very simple set up. Tiger .shp file as a layer. Has a join to an xlsx non geo attribute table as a .vrt .shp has join on MTFCC to MTFCC in xlsx.vrt. xlsx.vrt, has a string field with a brief label ...
1
vote
0answers
125 views

C++ QGIS Conditional Label Colouring

I am using QGIS and C++. When I create a layer of polygons with labels in the center I am able to use a RuleBasedRenderer to control the background colour of the polygon. How do I similarly control ...
0
votes
0answers
11 views

QGIS : On layers using my custom function and also having a Rule (Filter) the Vertex Tool is not working

I am using QGIS 3.16. To show my problem in details, I have made a very simple test example : Create New Shapefile Layer File name : Test Geometry type : Line OK Scale : 1:1000 Draw a line id=...
0
votes
0answers
26 views

Adding categories classification to rule

How do I add sub categories to a rule with automatic classification as I modify a field? Basically I want to give the chance to display each single new feature.
0
votes
0answers
24 views

Move labels with rules generate overlap

If I move the layer's labels with the move label tool my label is overlapping. The labels are categorized by rule My rule are based on two field "column1" and "column2" I can't ...
0
votes
0answers
100 views

How to set fixed distance labels from data defined centroid in QGIS (3.4)

I have a labelling issue in QGIS (using 3.4, but haven't tried in other versions). I have polygons for which I show an id number as well as some data information in the labels. I've used rule-based ...
0
votes
0answers
80 views

QGIS Rule-Based styles fail to render

I'm working with some Ordnance Survey data, specifically the VectorMap Local (in GML format, October 2018) set and attempting to style the layers using the very handy OS provided stylesheets (here: OS ...