Questions tagged [rule-based]
The rule-based tag has no usage guidance.
124
questions
0
votes
0answers
40 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
1answer
41 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-...
-1
votes
1answer
20 views
Using Rules to check NonBlank entries
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
34 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
96 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
67 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
50 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
37 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
24 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
43 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
14 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
43 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
82 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
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
1answer
70 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
83 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(...
0
votes
0answers
28 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 ...
10
votes
2answers
303 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
22 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
54 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 ...
1
vote
1answer
34 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
83 views
Symbology Based on Meeting Criteria
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
803 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 ...
4
votes
1answer
2k 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 "Primary" has '...
3
votes
1answer
74 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
154 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
41 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
145 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
66 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
52 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
35 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
63 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
248 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
41 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
104 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
108 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
337 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 ...
3
votes
1answer
69 views
Labeling only maximum value when zoomed out or print in smaller scale
I would like to prioritise the maximum values to be shown on the map. In other words, when the label collides it should drop out the minimum values.
In the shown examples, I would like to have ...
3
votes
1answer
78 views
Using the field calculator in rule based symbology
I am trying to categorise my site points by species group with rule based symbology;
e.g. bat uses the formula
"Group"='Bat'
But I would also like to have a different symbol for where there are ...
6
votes
1answer
169 views
Rule-based labeling with optional second field
I need to label some polygons with 2 fields using only one label:
The first being a field in the attribute table named "Bio-Code" the second one being optional if a cell in the field "BBT-Code" is ...
2
votes
2answers
244 views
How to export layers with rule based symbology with qgis2web
I am working as volunteer on a simple map for an NGO, I have some point layers with rule-based symbology. When I load these layers in qgis2web the symbology disappears, both in Leaflet and OpenLayers. ...
8
votes
1answer
198 views
QGIS can't detect negative values?
I'm working with the last version of QGIS (3.8.3-Zanzibar), and I'm trying to represent a Rule-Based Symbology from a CSV file with the following rules:
And the data from the prcptot column is this:
...
3
votes
1answer
274 views
Can qgis2web display rule-based layer style?
I’ve just made a map that has two layers: one that contains the polygons and other that contains points. For the last one, I used rule-based symbology where I define the size and colour of the points ...
1
vote
1answer
384 views
Line at map scale that do not vanish when zoomed out? (QGIS 3.8)
I'm drawing rivers and roads as linestrings with width set in map units from an attribute.
When zooming out, of course they vanish quickly, because 10, 20 or 100m is less than a pixel at 1:100,000
...
6
votes
2answers
703 views
QGIS styling a legend
I am a newbie working on QGIS 3.6 / Windows 10
I need to style a legend for map with headings and sub headings
The main divisions of the legend item need to be subdivided into sub-classes
i.e. The ...
3
votes
6answers
1k views
Rule based coloured background for labeling in QGIS
I am a newbie working on QGIS 3.6 / Windows 10. I need to label a polygon layer which is categorised by colour.
(pls refer to attached pic as a graphical reference)
The labels need to have a ...
