Questions tagged [rule-based]
The rule-based tag has no usage guidance.
161
questions
6
votes
2
answers
158
views
Representing five categories of data in one symbol using QGIS
I have been given the big task of representing a lot of data in one symbol. The plan is to represent 5 categories of data in one symbol.
I hope to do this by changing factors such as:
Fill colour
...
4
votes
3
answers
77
views
Categorized symbology with multiple variables (or nested categorization) in QGIS
I have a CSV spreadsheet containing thousands of rows, each corresponding to a georeferenced record of a lizard species. The dataset looks like the following table:
record sex age color ...
6
votes
2
answers
202
views
Updating symbol size units from mm to map units in rule-based symbology in QGIS
I have a quite complex rule-based symbology that is currently using millimetres as size units.
All third levels look the same, they just have different parents.
Is there a way to change symbol size ...
3
votes
1
answer
49
views
How to set up rule based offset points symbology in QGIS
I use QGIS 3.22.2 and I have points datasets of records from ecology surveys with column of "ID" of individual record and column "Species" with few different values (for example: '...
2
votes
1
answer
69
views
Categorized shapes for one attribute and categorized colour for another attribute
I can find similar questions but not the same and I'm struggling to figure it out.
I have species data for an area. The attributes I'm interested in displaying are the Species Group and the Species ...
0
votes
0
answers
68
views
Case When Rule-based Symbology
I am using the Expression in Symbology.
I have these attributes:
Num_blows which has specific numbers 30-40, next I have the
Blow Counts (Named as Set_1 up to Set_60).
If the Num_Blows is 30, there ...
1
vote
1
answer
48
views
Categorizing labels using same categorization as labeled layer in QGIS
I am using QGIS 3.28.
Use-case: I have a layer named: map_1, which is a map of many regions. The regions are identified with City_id. To distinguish the regions by their ID's, I first categorized them ...
1
vote
0
answers
74
views
Equivalent of QGIS' Rule-based Symbology in ArcGIS Pro
QGIS has a method to symbolize features called "Rule-based".
This method is super powerful because it allows the user to establish a list of rules to symbolize a layer's features. The user-...
2
votes
2
answers
61
views
QGIS based rules symbology with boolean options
I have a point layer with some boolean fields. I have created a symbol for each field when it is true.
However, when I create new symbologies for combined cases with more then one field true, I ...
3
votes
2
answers
110
views
Make a style rule that tests for a child having an attribute with a given property
In QGIS/QField, I have a feature (plants) with child features, which are dated observations of the plant, and I would like to make the appearance (color or shape) of the feature depend on whether ...
1
vote
1
answer
62
views
QGIS Rule Based Labeling filter string from a value
I'm relatively new to QGIS. Recently I started mapping the hiking trails of Nepal. I used a GPX recorder application from Android Play Store. While entering the waypoint, I entered the name. The ...
5
votes
2
answers
149
views
Show single label for features grouped by identical attributes in QGIS
I have a database with of accidents in an area. I want to show a lable with the type of accident for every occurence. In the database there are multiple entries for the ID in the first column (because ...
2
votes
1
answer
137
views
Update rule-based symbology QGIS
Goal: be able to update ruled based symbology
Data (layer attribute table): a column with the ID of the individual, a column with the date of identification (Year-month), a column with the name of the ...
5
votes
1
answer
62
views
Dynamically style polygons in a vector grid based on value of adjacent polygon in QGIS
I am trying to achieve a solution to display spatial relations in a vector grid using rule-based styling similar to the image below:
I create the grid with the Vector>Research Tools>Create grid....
1
vote
0
answers
72
views
Rule-based labelling in QGIS not working
I have a map of the Isles of Scilly, I have geopackage data such as 'points of interest' that show me the island names and other places on the islands. I am trying to change the labels so that the ...
1
vote
1
answer
70
views
Rule-based symbology label to map labelling
How to import values from 'label' in symbology window to showing them as particular labels (QGIS 3.22)? I suppose it can be done with some short, clever expression in labelling window.
0
votes
0
answers
119
views
QGIS - Rule based symbology, four symbologies from two fields with several acceptable values
I have access to a remote service, with a polygon layer that i need to organize. The service is a REST service, and the setup of the data fails to load into QGIS (which is acceptable, as REST is ...
4
votes
1
answer
99
views
Getting all symbols to render when using Point Displacement in QGIS
I created a series of rule based symbols that allows me to display two pieces of information on the same symbol. Basically, I have one column coloring the top half and one column coloring the bottom. ...
1
vote
0
answers
34
views
Toggle on/off rule based labeling in PyQGIS
I have a vector layer. It's defined with rule based labeling.
I need to control the rules to turn on / off programmatically.
How to do it?
0
votes
1
answer
41
views
QGIS Bézier-editing plugin does not honor id-creating rule when saving new line feature
I have started using the QGIS Bézier Editing Plugin by Takayuki Mizutani v.1.3.4. Plotting line features in my project works well, but on saving the feature the attributes dialog is empty, whereas ...
1
vote
1
answer
49
views
Rulebase symbology: Differentiated symbologies for same polygon layer presented based on hierachy (QGIS)
TL;DR: Creating nice symbologies for a single layer, where a dotted line doesn't display underneath a dashed line, for sections where the dashed line is a symbology for a larger, more important area. ...
0
votes
0
answers
56
views
How to Write Rules in City Engine
I have just recently started using City Engine, and I am at complete loss of how to write rules. I have a shapefile, which a polygon file of buildings outlines. In the layer there is an attribute ...
1
vote
0
answers
14
views
QGIS issue with rule based styling on MacOS
I regularly encounter a strange behavior in QGIS (3.16.8-LTR but also in former versions) when using multiple rule-based styling options. I'm working on MacOS (10.15.7).
In the layer display pannel ...
1
vote
0
answers
35
views
Style rule based on qgsfunction not working in QGIS 3.22 #92
I'm using a QGIS style based on a function which returns the value of a layer variable passed through a pyqgis plugin :
@qgsfunction(args="auto", group="toto")
def color_trajecto(...
3
votes
1
answer
223
views
Creating rule-based style for attribute between two values in QGIS
It seems a pretty straightforward rule but I believe I am missing something simple. Let's say I have, in my attributes table, an attribute called "NumberOfFloors", with values between 1 and ...
1
vote
0
answers
63
views
QGIS rule-based filtering not working
I'm having a problem with rule-based filtering in QGIS. I created a rule and tested it, and it showed that it gets hits. Below shows the attributes to which I wish to apply the rules:
The following ...
3
votes
1
answer
141
views
Highlight polygons using comma delimited text coordinates QGIS
I am new to GIS. I have significant CAD experience and some limited Python knowledge, and am generally familiar with basic QGIS functions.
In short, I will have several CSV files containing co-...
7
votes
3
answers
405
views
QGIS labels with multiple rule based icon
I'm learning QGIS. I have drilling locations showing on a map with a specific SVG icon (D1 and D2). I also have my labels showing the name of the soil sample taken in each drilling and the ...
2
votes
1
answer
86
views
"Rule-based" background color in QGIS attribute form containers?
In QGIS attribute form Drag and Drop Designer we can choose a backgroud color for widget containers (Tabs and Group boxes):
Is it possible to have rule based background colors depending on some ...
1
vote
2
answers
76
views
Rule-Based layers not displaying in the correct order
I am having trouble with bottom layers overlapping upper ones within a rule-based layer. (screen showing the issue) It used to work just fine, I was able to create new polygons under ones previously ...
1
vote
1
answer
254
views
Group style groups within on layer in QGIS
I created a complex style for a layer using rule based styling. In the original project, the layer is presented in the layers panel the same way it is displayed in the layer properties, that means ...
3
votes
2
answers
172
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
0
answers
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 ...
3
votes
1
answer
148
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
1
answer
166
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
2
answers
277
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
0
answers
84
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
0
answers
210
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
1
answer
112
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
1
answer
229
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
1
answer
31
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
0
answers
102
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
3
answers
586
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
1
answer
32
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
1
answer
125
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
2
answers
243
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
1
answer
103
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
0
answers
188
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
0
answers
36
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
0
answers
62
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 ...