Questions tagged [dissolve]
To merge features based on specified attributes.
387
questions
2
votes
1answer
37 views
Dissolve has one county outline
I'm new to QGIS and I'm trying to create a statewide map using specific regions, which break down by county. The steps I'm using are:
Vector Geometry: Fix geometries
Vector Geometry: Delete holes
...
1
vote
0answers
25 views
Adding attributes from surrounding feature (exclave problem)?
Here is the problem:
I am creating polygons based on the result of closest facility tool in Arcmap. Polygons consist of municipalities with the same closest hospital (impedance is a travel time, not ...
1
vote
2answers
77 views
Merge polygons based on Field A or Field B
I have a parcel layer I need to dissolve based on Owner OR Postal Address.
I know I can always dissolve based on Owner AND Postal Address, but that is not what I need.
So if:
owners are different ...
2
votes
1answer
94 views
How to dissolve overlapping polygons using GeoPandas
Assuming the following:
from shapely.affinity import translate
from shapely.geometry import Polygon
import geopandas
p0 = Polygon( [(0,0), (2,0), (2,2), (0,2)] )
p1 = translate(p0, xoff=1)
p2 = ...
1
vote
0answers
42 views
Use of QGIS/GRASS/SAGA procedures on Geometry Generator
Im new at QGIS, started 2 weeks ago. I'm trying to automatize the display of a map and get rid of some "duplicated" layers and all the extra work. I need to know if SAGA's dissolve can be used in the ...
3
votes
1answer
42 views
Calculating field while dissolving
I have two polygon Layers, A and B correspondingly. The polygons of B are lying on top of layer A and also overlapping the polygons of A (I made an example of the attribute table for better ...
0
votes
0answers
23 views
GeoPandas Dissolve splits polygons into parallel strips?
I have polygons that is converted from raster dataset with Raster Pixels to Polygons in QGIS. I would like select some polygons based on the attribute value and merge them using Dissolve function in ...
1
vote
0answers
41 views
Merging adjacent polygons using Geopandas by avoiding filling gaps
I have raster dataset that I would like to convert into vector polygons. Raster to polygon conversion works pretty good. But, having problem when I try to merge adjacent polygons using Dissolve ...
2
votes
0answers
39 views
Preventing gaps on polygon shapefile being filled automatically when exporting from QGIS?
I classified raster dataset and converted raster dataset into polygon shapefile, then merged adjacent grid polygons using QGIS Dissolve function (figure 1) creating a temporary file. However, when I ...
0
votes
0answers
80 views
Dissolve output not dissolved in ArcMap?
Even though polygons of an input feature have the same attributes/dissolve fields, the output does look like in the picture below.
Does anybody know what the problem is?
This problem occurs only in ...
4
votes
1answer
112 views
Selecting which polygon's attributes to keep after dissolve
I have two polygons, after doing a dissolve I can't choose which polygon's attributes the new dissolved polygon will have. I tried to find a pattern by checking if the bigger's polygon attributes are ...
0
votes
0answers
35 views
Creating shapefile based on map with ArcGIS Desktop?
I'd like to create a shapefile with ArcGIS of the map attached below. Published in an econ paper, the map divides the territory of the German Union (post 1815) in 19 states (more precision can be ...
0
votes
2answers
62 views
GeoPandas sjoin with extensive quantities
I have one geodataframe that contains polygons and corresponding land use category (e.g. agricultural, commercial, retail, residential, ...) and another that contains census tract polygons and ...
1
vote
0answers
24 views
QGIS dissolve/merge features by all attributes
I have a vector layer with thousands of features and over ten columns (attributes). I would like to dissolve/merge features with identical attribute combinations and keep the attributes. I think it ...
1
vote
0answers
43 views
Fill in gaps in QGIS shapes?
So basically, I've written a script that generates a lot of polygons over the UK with certain criteria. The output it a lot of shapes like the following - I wanted to know if, in QGIS, I'm able to ...
0
votes
0answers
33 views
ogr2ogr sqlite dialect can't find functions
my question might be related to this Dissolve using ogr2ogr gives 'no such function: ST_union'
What I am trying is st_unioning my landparcel polygons based on its group.
The code is very ...
1
vote
1answer
99 views
Problems with dissolving layers [QGiS 3.4.1]
I am currently working on a set of data that defines restricted areas for use of photovoltaic modules.
This set of data amounts to 270.00 polygons in total [with their own geometry].
For simpler ...
1
vote
1answer
49 views
Merging polygons without losing area using ArcGIS Pro?
I have a shapefile with 23 polygons,I want to merge them and get the total area of this big polygon.
But when I used "merge"tool, it only merge polygons but area.
Any ideas about what I should do?
0
votes
0answers
32 views
QGIS Dissolve tool erroneously fills rings in polygons
I have a shapefile layer with >27,000 polygons. I want to dissolve these together to create a footprint layer. The Dissolve tool works fairly well, but it has filled in what should be rings in the new ...
1
vote
1answer
45 views
Regroup multiple polygon with same attributes in one
After looking for an answer on some forums (without success :/) i post here in hope on of you can help me.
I have a polygon shapefile with thousands of entities (=row) and >10 attribute column.
A ...
1
vote
1answer
37 views
Quicker function than dissolve and difference
I'm on QGIS (v. 3.6) trying to create a map of Florida's hydrography using the NHD "Water Areas" shapefile. Methodology is to fix any invalid geometries in the NHD data, dissolve the layer, and then ...
0
votes
0answers
83 views
Improving speed of GeoPandas dissolve?
I am trying to dissolve grid spaces by category using GeoPandas' dissolve function, but it doesn't finish after hours of running and I want to make sure I'm not doing something wrong and/or there isn'...
1
vote
0answers
97 views
QGIS 2.18.28 Dissolve Error: “-2147483645 See log for more details”
I am doing property research on a county in Texas. I have all the parcel data and am trying to dissolve by Owner Name so that I can use the info tool to quickly see all the properties a given person ...
2
votes
1answer
43 views
Erasing boundaries between polygons that are next to each other using QGIS?
I have files that representes individual houses and blocks. I want to have a file that represents a residential area in a block.
Is there a way to erase the line, boundaries, between polygons that ...
2
votes
1answer
53 views
QGIS (merging, dissolve, union) lines of same name
I have street data where roads are segmented for no particular reason. I want to merge, dissolve or union whatever seems fit to make a single flat line. I H
have tried above processes in QGIS but ...
0
votes
0answers
16 views
ArcMap Model with parameters
How do I get the fields from the intersect results in my arcmap model to appear as the possible 'statistics fields' for my dissolve tool when using model parameters?
I have the statstics field set up ...
1
vote
0answers
73 views
Unary union/Dissolve returns null geometry in QGIS 3
I am writing a python processing script in QGIS 3. In it, I have polygon geometry objects stored in a list polygonGeoms and I want to dissolve all of it into one geometry. However, when calling the ...
2
votes
1answer
124 views
How to dissolve shared line segments together in QGIS?
I have 2 features which are lines on a single layer re-projected to ESPG:2039.
I wish to combine them into one MultiLineString but in a way that their common part is merged to a single LineString. I'...
2
votes
1answer
34 views
Counting the number of shared point within polygons [closed]
I have a set of points on a map, each with a unique location id, with one or more points within a number of polygons with unique polygon ids. I am trying to associate each location id with the number ...
2
votes
0answers
89 views
Dissolve Line Strings to one string - “No Shapely geometry can be created from null value”
I have a layer with 7000 LineStrings, all represent bus routes:
It seems that all the bus routes are contiguous, but I'm not sure of it.
I'm trying to use python shapely to dissolve all those ...
2
votes
2answers
53 views
Dissolve with common value in a field and not common in another
I have a shapefile in QGIS and I want to dissolve it with the options:
A field named 'specialid' has the same value
A field named 'city' has different value
Ok the first is very easy. It is ...
3
votes
1answer
99 views
Dissolve (merge) polygons QGIS based on attribute values only when are adjacent
I am a fairly new user of QGIS having a question regarding dissolve functionality.
I am working with the NUTS-2 shapefiles provided by EU, which I have imported in QGIS. I have created a new layer ...
2
votes
1answer
76 views
Dissolve (merge) polygons QGIS based on (non exact) attribute values
I am a fairly new user of QGIS having a question regarding dissolve functionality.
I am working with the NUTS-2 shapefiles provided by EU, which I have imported in QGIS. To ease the discussion, I ...
0
votes
0answers
34 views
QGIS dissolves all different shapes into one feature instead of multiple features [duplicate]
I'm pretty new to QGIS and geoprocessing. I have a layer of points representing traffic lights - where each point is a different feature:
I wish to create a layer with traffic light junctions based ...
0
votes
0answers
36 views
Retrieve attribute with max value by group
I have a intersected counties shapefile with wind potential category attribute. What I want to do is to dissolve the features grouping them by county, and retrieve the WPC value which has the largest ...
0
votes
0answers
39 views
Dissolve polygons using clustering
The attached vector file contains thousands of individual polygons (a byproduct of the underlying raster image). The result of using polygonize function in qgis. My intent is to dissolve the polygons ...
2
votes
1answer
159 views
Dissolve Field Not Showing in QGIS?
Using QGIS 3.6
Currently trying to dissolve a polygon layer by FIELD values. QGIS 3.6 and the fields won't show up. In fact I am unable to dissolve by FIELD for any layer in my entire project.
If I ...
1
vote
0answers
18 views
Dissolve on attribute field and location?
I've got a county parcel shapefile and I'm wanting to find all the properties over 300 acres. When I dissolve based on ownership and search for dissolved properties that sum over 300 acres, some of ...
0
votes
1answer
320 views
Dissolving polygons to single part features with Python (shapely and fiona)?
I used the code from Dissolving polygons based on multiple attributes with Python (shapely and fiona)? to dissolve a shapefile using shapely and fiona. However the output creates multi-part geometries....
1
vote
1answer
36 views
Filter options are not saving in Dissolve algorithm window through Graphical modeler in QGIS 2
I am working on my project in QGIS 2.18 through Graphical modeller and using some basic algorithms for polyline objects.
However, I do not understand why specification for Dissolve algorithm cannot ...
1
vote
1answer
150 views
How to remove artifacts with SQL Server GEOMETRTY::UnionAggregate()
We'd like to do an effective "real-time dissolve" on an Esri feature class with a SQL GEOMETRY shape where a parcel layer is "dissolved" into products using an attribute (ProductID) of the parcel ...
5
votes
1answer
167 views
Using Dissolve and Multipart to Singlepart in QGIS?
I started with a network of polylines.
In QGIS I used dissolve to 'merge' all lines according to an attribute value. This did exactly that, but included non-connecting lines which I don't want. I ...
1
vote
1answer
143 views
Merge connected lines and split them after set unequal distances
I need to edit line features in QGIS 3.4.4. I have more than 1000 line features that I want to first merge and then split. The line features describe roads in useless intervals, my goal is to ...
0
votes
0answers
38 views
Dissolving GeoJSON with nodes and lines to one average line?
I have a GeoJSON with two layers. One with lines and one with nodes. I'd like to dissolve it (or at least the layer with the nodes) to one single line, by averaging the positions.
I've looked at Turf....
0
votes
1answer
287 views
Dissolving featurecollection in google earth engine?
Here is the link to my GEE code:
https://code.earthengine.google.com/99b494aacf00df398e0e710ec02c13e8
Here is the code (DMDP is an asset and to see it please follow the link):
Map.centerObject(...
1
vote
1answer
69 views
Mapping Commuting Zones from Counties for US 1990 Data in ArcMap?
This question follows Seeking 1990 US Commuting Zone shapefiles?
I am attempting to map US commuting zones as defined in 1990. I have successfully mapped counties from a county shapefile obtained ...
2
votes
1answer
117 views
QGIS: Dissolve after raster-to-polygon not working correctly, only dissolving a portion of the vector layer
I am working with QGIS and am trying to convert a raster layer into a vector layer. I have converted it to a polygon from raster (image below), and then wish to dissolve this polygon into a single ...
1
vote
2answers
41 views
Dissolve everything except for one particular polygon
I want to dissolve these polygons (column FIRST_N03_003) except for FID 34 and 77.
Essentially, the 003 column is the state, and the 004 column is the city, but some cities are independent and do not ...
1
vote
0answers
218 views
QGIS: Dissolving Polygons with Self-Intersection
I have created multiple polygons with some subset of track-lines, with the order of time those points were recorded. Therefore some of the polygons have self-intersection within the polygon.
Is there ...
1
vote
0answers
62 views
Promoting to multipart using PyQGIS?
I am creating a code that aggregates neighbouring polygons if they have similar value on the field 'DN' and if they are closer than 50 m.Then I want to iterate this 3 times.
I could already get the ...
