Questions tagged [classification]
The process of sorting or arranging entities into groups or categories; on a map, the process of representing members of a group by the same symbol, usually defined in a legend.
734 questions
0 votes
1 answer
57 views
Error classifying an array using ImageCollection().toArray()
I have an ImageCollection() that I converted to an array with .toArray. However, when creating the training and test samples, I get an error: "Number (Error) Input array has length 146 on axis 0, ...
- 514
0 votes
1 answer
52 views
Sampling pixels in a collection of classified images
I am training a Random Forest model and classifying a collection of about 400 S2 scenes. I end up with an ImageCollection, containing the original spectral bands and the classified band layer. To ...
0 votes
0 answers
47 views
Unsupervised classification over really large large area in Google Earth Engine
I have a problem with large area that i am trying to classify. The problem is: FeatureCollection (Error) Computed value is too large. What can i do to classify this area? I added img of the area and ...
1 vote
0 answers
63 views
Supervised vector classification in QGIS
There are lots of tools and plugins to classify raster data (mostly satellite imagery) in QIS, but I am looking for a tool (or workaround) to assign classes to vector features based on attributes, ...
- 930
2 votes
1 answer
91 views
Cluster symbol color based on most frequently occuring class
This earlier post was really helpful: Cluster symbol color based on categorised variables But I would have an additional requirement: If the points are from mixed classes then @cluster_color will be ...
- 23
0 votes
0 answers
29 views
SCP preview accurate but final raster shows fewer classes after classification
I’m using the Semi-Automatic Classification Plugin (SCP) in QGIS for the supervised classification of Landsat 7 imagery (2001). The Preview Classification accurately shows all expected classes (e.g., ...
0 votes
1 answer
57 views
PDAL Coplanar in a WHERE statement?
I can't get Coplanar = 1 to be accepted in a WHERE condition in PDAL. I can run filters.approximatecoplanar, and I can use Coplanar in a range statement ("limits":"Coplanar[1:1]")....
- 21
0 votes
1 answer
110 views
Classifying layers based on colours of a raster image on QGIS
I would like to make individual vector layers based on colours of a raster image. The colours are defined, for example houses/buildings are light brown, forests/grassland is green and the urban area ...
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0 answers
30 views
Moving samples between classes in eCognition 9.01
I’m currently using eCognition 9.01 and have encountered an issue with transferring samples between classes. Here’s the situation: I collected samples for a class called Ck and wanted to duplicate ...
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1 vote
0 answers
78 views
Classifying spatial data using QGIS [closed]
I have two files: geologie.dbf and Legenda_Geologie.xls. I need to classify some regions within the area that I am studying but I am not exactly sure how to do that. Do I need to manually type the ...
- 11
1 vote
1 answer
65 views
QGIS expression to symbolise road condition between values
I am using QGIS 3.22.16. I try to symbolize a road condition. The result wanted is: Equal 2 if Minor > 0.3 Moderate > 0.2 severe > 0.1 Equal 1 if 0.2 < Minor <0.3 0.1 < Moderate <...
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0 votes
0 answers
51 views
How to classify points in a QGIS shapefile by size based on a numeric attribute (tree canopy diameter)?
I'm using QGIS 3.28. I have a shapefile containing point data, where each point represents a tree, and I want to classify these points by size on a map. Specifically, I have a numeric attribute for ...
- 173
2 votes
1 answer
134 views
Defining not-custom graduated style to polygon layer in PyQGIS
I'm writing some scripts on the PyQGIS 3 console to build a plug-in and I would like to create a color-graduated style for my vector layer. I read Applying graduated renderer to polygon using PyQGIS, ...
0 votes
0 answers
91 views
Classification based on two attributes in QGIS
I am using QGIS occasionally to illustrate landscape analyses, assessments and resources. Nothing too fancy at this stage. I have been wondering how I can classify my map based on two attributes. In ...
- 1
0 votes
1 answer
66 views
Supervised classification ALOS-PALSAR Google Earth Engine
I need to create a supervised classification for flood detection with ALOS PALSAR in Google Earth Engine. How can I do this?
