Questions tagged [rule-based]
The rule-based tag has no usage guidance.
133
questions
3
votes
2answers
91 views
Referring to rule style in expression string builder in QGIS
I'm working with QGIS 3.16 Hannover.
I've got a rule-styled polygon layer cuadric_cabañ. Rules are:
overlay_intersects(layer:='habitat_caba',filter:=(CODIIGE=210 OR CODIIGE=320))
overlay_intersects(...
0
votes
0answers
25 views
Buffer around lines with rules or expressions
I need to create buffers around a layer of lines that represent infrastructures and they are symbolized according to the type (roads, railway, waterway and electric cables). Is there any way to create ...
2
votes
1answer
36 views
"Eval Error" when selectively rendering raster layers in QGIS Atlas
Using the Atlas feature in the QGIS print composer, it is possible to use rule-based symbology to show/hide components of vector layers as required or defined by the Atlas?
I have multiple pages, ...
5
votes
1answer
59 views
Propagating symbology changes made with PyQGIS to Layer Styling Panel
I am using a script to change the opacity on a rule-based symbology.
layer = iface.activeLayer()
opacity = 0.2
if layer.renderer().type() == 'RuleRenderer':
renderer = layer.renderer() #...
3
votes
2answers
66 views
QGIS rule-based labelling base on active map layers
I'm new to QGIS.
I'm currently using the new version 3.20.0 Odense and I have some troubles setting up the rule-based labelling for a layer.
Essentially, what I need is to automatically swap labels ...
1
vote
0answers
55 views
Rule based symbology in QGIS [closed]
I want to make a rule-based symbology with two classes: one class with all the empty cells in a given column and one class for the cells that do have a value in it.
In Excel I would use something like ...
3
votes
0answers
45 views
Auto updating rule based symbology categorised by date
I have a shapefile of "Detection Points". These have a "strength" attribute and a "date" on which each was made. Data collection is ongoing - that is it began in April ...
4
votes
1answer
63 views
Filtering on centroid distance between layers in Rule based layer styling in QGIS
By using Rule based layer styling for a polygon shapefile I want to display only those features whose centroid is separated by 1.000m from the feature centroids of another polygon layer ('layerB'). ...
2
votes
1answer
108 views
Rule-based symbol for point within polygon in QGIS
I would like to use a set of rules to draw features from a point_layer that are within a polygon_layer.
Points that answer true to
("VAL_PROTECTION_EP3" = '1' AND "TYPE" = 1)
...
1
vote
1answer
26 views
Setting expression for two different table attribute to store as default style
I'm new on QGIS. I would like to store a default style in geopackage use by two different table attribute. First table with "building_height" , and second table with "block_height"....
0
votes
0answers
49 views
How to efficiently filter and select attributes based on conditional formatting?
I am wishing to filter my attribute table to display only certain values that meet certain criteria based on multiple column values.
For example, I want to show all locations on my map that are Lost ...
0
votes
2answers
169 views
Rule-based styles don't work in QGIS (points don't appear)
I took a very good course on QGIS from Udemy (GIS in QGIS 3 for beginners) and made a pretty complex map with it. A month or so afterwards, I made a pretty simple map without any problems using a rule-...
-2
votes
1answer
29 views
Using Rules to check NonBlank entries in QGIS [closed]
I am trying use Rules in Symbology to display entries based on a criteria. The criteria is display only those entries which have a date associated with them. I have table of points which has Date ...
1
vote
1answer
55 views
PYQGIS rule-based renderer with SVG symbols
I am trying to create a rule-based renderer with different SVG icons for each class. For some reason, I keep getting the error :
Rule' object has no attribute 'QgsSvgMarkerSymbolLayer'
Why do I get ...
4
votes
2answers
123 views
Setting different font color types from the same field in rule-based labeling in QGIS
Trying to set different font color types from the same field in rule-based labeling in QGIS.
I have a "C°" field with only 2 values: +56.7 C° and -89.2 C°.
Trying this expression to have it:
...
2
votes
1answer
78 views
Usage of QgsRuleBased3DRenderer with PyQGIS
I'm trying to use QgsRuleBased3DRenderer with PyQGIS in order to set different color in a 3D view.
I'm trying to make something similar to this but with the 3D syntax (here is the 3D syntax: https://...
0
votes
0answers
88 views
QGIS - label color setting
I use rule-based labeling with geometry generator on line layer. I use expression @symbol_color, because I want to have color of labels the same as color of lines. However, @symbol_color doesn't work ...
0
votes
0answers
42 views
QGIS rule-based labeling with callouts
I have line layer with callouts created in geometry generator. Then I create labels created by expressions rule-based labeling. How can I create expression refering to labels with callouts ? I want ...
0
votes
0answers
26 views
Merged Shapefile with different Styles
QGIS Zurich 3.18.2 Need to pass on a Shapefile to A Nother. There were three Layers each with assigned Label Style (saved) as can be seen
Yes I know I have a lot more work to do on the Label placement/...
0
votes
0answers
44 views
Cannot Load Rule Based Label with QGIS
Working with QGIS, I saved my Rule Based Label as a .qml file. Opened a new Project Loaded the Shapefile and then Loaded the Style .qml file but it lost its rule based styling, x and y displacements ...
0
votes
0answers
22 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=...
3
votes
0answers
48 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 ...
1
vote
2answers
130 views
Rule-based symbology based on related layer in QGIS
I'm working with QGIS
I have two layers:
Layer 1: has the id and geom columns (multypolygon layer)
Layer 2: has the id, gid and type columns (table layer).
The value gid of layer 2 is the foreign ...
2
votes
1answer
20 views
Marker line in rule-based layer?
In a line layer, which is rule-based rendered : As I can see it, it is only possible to ad simple lines. I want to ad a marker line. Is that not possible ?
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.
3
votes
0answers
22 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 ...
4
votes
1answer
98 views
Stretch label all along line length
I need to know if in QGIS 3.16 there is a method to stretch a label all along line length.
My layer has lines with different length and I want to know if is possible to stretch automatically labels ...
5
votes
1answer
107 views
Removing an empty entry rule by using QgsRuleBasedRenderer without affect other rules filled in PyQGIS?
I create rules with this code but it creates one more but without data and when using root_rule.removeChildAt (0) it deletes a correct one.
layer = iface.activeLayer()
symbol = QgsSymbol.defaultSymbol(...
10
votes
2answers
491 views
Rule-based symbology based on current selection in QGIS
I have two oracle layer (point(p1) and polygon(pl1)). I want to build a rule-based symbology which is based on current selection on two cases:
Case 1- When I select a point from table p1, I want that ...
3
votes
1answer
85 views
How can I load and draw predefined chart images (diagrams) rule based and related to a point vector layer with QGIS
I have a bunch of diagrams for a set of route segments, stored as PNG, PDF or SVG with a regular name (topic-segment-id.(png|pdf|svg) for example), representing a certain aspect (like crossing rate or ...
1
vote
0answers
26 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 ...
2
votes
1answer
64 views
Rule Based styling with different forms and colors
I have a map about different locations of amphibians. I want that the colors illustrates the specific species and the form illustrates the stadium (young, adult). I know how to give different colors ...
2
votes
1answer
42 views
QGIS Symbology: how to make a symbol a shape according to a set of rules and a color according to another set of rules
I'm using QGIS 3.14 with GRASS 7.8.3. I have a data set with point coordinates on a plan (artifacts on an archaeological site). I have two main variables that I want to show. So, I'd like to have the ...
2
votes
2answers
94 views
Symbology Based on Meeting Criteria using QGIS
I have a dataset that includes populations and subpopulations, so for each main population there may be several subpopulations. I have organised this in the table so that a population has the same ...
8
votes
1answer
1k views
Place label along line near start and end of line in QGIS
I have four fields managing the numbering of the start and end of road sections.
I created two label rules, one for the start and one for the end of the road sections.
I set the position of the ...
5
votes
1answer
3k views
Rule-based symbology in QGIS
I'm trying to create the following rule based expression for displaying a line:
if column "riparian Veg" has a 'Yes' entered into it then display the line but if another column titled "...
3
votes
1answer
94 views
Applying Rule-Based Style taken from another layer to layer with no geometry
I have two layers
"Suburb_Type", that has more than 1000 suburbs in shapes and is styled with categorisation rule. (columns: 'suburb_code', 'geometry', 'category_variable')
"Suburbs_in_Study", with ...
1
vote
2answers
187 views
Qgis 3 - Rule-base labeling combining to backgrounds
I have a pointlayer with no symbology, but is labeled by numbers 1-74. The labels is styled with a circle background. For some of the points I need to keep the circle, but add a small SVG-symbol to ...
1
vote
1answer
49 views
Change/Hide the pen width for line shape file based on rule in QGIS
I have line shapefile, in which I have a condition to display line's width based on a rule as shown in the image below. But in this case I was not able to define line width to 0, it is taking hairline ...
0
votes
1answer
192 views
How to run multi level segmentation for LULC in process tree, eCognition software
Can we run the eCognition multi level (level 1 ,level 2,...) segmentation and classification in the same process tree? I want different outputs to show for each levels in a process tree. I'm in the ...
1
vote
0answers
74 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:
...
0
votes
1answer
55 views
Labeling by using different columns
I try to label a layer by using a rule based labeling. What I specifically try to do is to find an expression which says:
"If column 1 shows the attribut x then label layer "Test" by the attribute of ...
1
vote
1answer
43 views
QGIS different scale levels in rule-based styling - in one rule
I have a layer with 4 roadclasses. For this layer I created a rule based symbolization, with 4 rules. In every rule I filter another roadclass and set a different symbolization and scale for this rule....
1
vote
1answer
74 views
QGIS rule based styling - rule ordering
I’m experimenting with some rule based styling which is working really well to a point but I’m hoping it can do more. I work in school transport I’ve plotted all pupils in a certain school on the map. ...
1
vote
0answers
25 views
QGIS 3.4 - Symbology expression for features that have not been styled by rules [duplicate]
I have a rule based set of expressions for styling a map according to the contents of the 'Layer' field. e.g if the Layer starts with a 'C'
"Layer" ILIKE 'C%' colours the line red.
Is it possible ...
3
votes
1answer
305 views
Using Rule-based/Geometry generator style in QGIS
I have layer for comments in qgis, symbology style is rule based with Geometry generator.
Problem is with displaying name in layers tab because the line before text is too long
How do I solve the ...
1
vote
0answers
43 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 ...
2
votes
0answers
128 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 ...
0
votes
0answers
139 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 ...
5
votes
2answers
447 views
Save Rule Based Symbology as Default Layer Style
I am constantly moving layers in and out of my projects, I was able to set default style for layers and they all the layers I drag and drop to my project get the same style by default.
Lately I have ...
