All Questions
117
questions
0
votes
0
answers
27
views
"ERROR: 22001: value too long for type character varying(6)" for polygon shapefile
I am facing an error
ERROR: 22001: value too long for type character varying(6)
while uploading a shapefile to online govt. portal. When I asked the person only mentioned that there is problem with ...
2
votes
0
answers
62
views
Why are there so many slivers in my polygon shapefile?
I georeferenced a map and then traced a vector polygon shapefile over it, but when I dissolve it I am left with an enormous amount of slivers. All the vertices are snapped as far as I'm aware. What ...
2
votes
1
answer
140
views
How to identify holes of missing geometry enclosed within a polygon in QGIS?
I want to locate or highlight all the holes (invalid interior rings that do not connect at all vertices and edges) and redundant geometry in a polygon shapefile in QGIS so that I can go back and ...
-1
votes
2
answers
191
views
Locate or find holes tool in QGIS for polygon shapefiles [closed]
I want to locate or highlight all the holes (invalid interior rings that do not connect at all vertices and edges) and redundant geometry in a polygon shapefile in QGIS so that I can go back and ...
2
votes
0
answers
37
views
Merging smaller polygons into bigger surrounding polygons in QGIS [closed]
I am using QGIS 3.34.2 (Prizren). I am using a village-level shapefile which I downloaded from SHRUG. I have to use only the villages in West Bengal for an analysis. Furthermore, I need to combine the ...
0
votes
0
answers
39
views
Problem with create line tool in QGIS, creates an undeletable line that is not part of any layer
I was attempting to edit a shapefile layer in QGIS. I used the "create line tool" and started to sketch out a shape. I didn't like how it was turning out and tried to cancel it by pressing &...
0
votes
1
answer
50
views
What is meaning of extra bytes in .shp file or how to calculate content length
I'm trying to read a .shp file. That .shp file contains polygon type. So I read all the records perfectly, after the reading the points, end of the file that have some 28 bytes are there what is ...
1
vote
1
answer
132
views
Create a map of time since fire in QGIS
Using QGIS I want to create maps which visualise the fire history of an area, in particular the time since the last fire.
I have a shapefile which contains polygons of each fire that has occurred in ...
0
votes
0
answers
44
views
Buffer output issue QGIS
I'm using QGIS 3.18 version. I tried to use the buffer tool with the centerline (provided for a sample) of the road.
I found overlapping of buffer polygons and some unusual shapes of polygons too. I ...
2
votes
0
answers
49
views
QGIS highlighted cell issues
Does anyone know why this is occurring? I obviously want the yellow highlighted polygon boundary to be always on top. Currently, the non selected shared boundaries are rendering on top of the ...
2
votes
1
answer
175
views
Creating new layer with custom regions from states boundaries in QGIS
I am trying to create a map where I can combine a layer of states boundaries and one other with custom regions (Est/West) on QGIS.
So I have tried it in different ways (union, intersection, merge ...
1
vote
1
answer
663
views
Data from map and attribute table disappeared after saving
I am relatively new to QGIS and have been doing some simple georef and digitising work. At the start I lost a lot of data, as I hadn't saved properly, and I have been constantly saving ever since.
...
3
votes
1
answer
515
views
Merging polygons of different layers with QGIS
On a map, I've created several polygons to mark some areas. Each polygon (shapefile) is on its own layer.
How can I merge the polygons, so that one layer consists of multiple polygons?
I can't select ...
1
vote
3
answers
641
views
Export polygon from shapefile as type: 'Polygon' (not type: 'MultiPolygon')
From a shapefile I try to export the contained polygons to GeoJSON. This works fine with right click on the layer > Export > Save as ... > Format: Geojson. The exported file then looks like ...
1
vote
1
answer
914
views
Deleting lines in polygon shapefile using QGIS
I have a polygon shapefile. After dissolving a few polygons I got some unrequired lines inside one of the polygons that I couldn't delete. When using the vertices tool the lines don't show and ...
2
votes
1
answer
44
views
How to determine data used for plotting polygons in QGIS
I have this shapefile of soil characteristics in Massachusetts, but when looking at its attribute table, I can't determine what values are being used to plot each polygon. This becomes an issue when I ...
2
votes
1
answer
865
views
Splitting feature into individual features in QGIS
In QGIS I have a layer that is made up of a large number of polygons that are merged together to form one feature. Is it possible to split this feature into the individual polygons that make it up so ...
3
votes
2
answers
1k
views
Selecting points which touch "boundaries" of another polygon using QGIS
I have an quite complicated polygon shapefile and a lot buffers around points (second shapefile).
These small polygons are within and outside of the big polygon. I need to select those polygons which ...
1
vote
0
answers
392
views
QGIS. Combining points data on a map with attributes in polygons
I have a project where I'm trying to combine flood risk data to a list of postcode (/zipcode) data. The postcode data is a csv that contains each postcode's easting, northing, longitude, and latitude ...
2
votes
1
answer
268
views
Rendering NULL values with joined CSV file in QGIS
I have a set of polygons in a single shapefile layer. I have added a data table as a new layer and joined the two layers. Some of my polygons do not have entries in the data layer and consequently, ...
2
votes
0
answers
108
views
Dissolving polygons within another polygon in QGIS
I have multiple pixels in a shapefile 'delete_pixels.shp' that are within a different polygon 'delete_id.shp'.
I would like to dissolve the pixels that are within the polygons of 'delete_id.shp'. ...
0
votes
0
answers
298
views
Can't see polygons of a shapefile but attribute table is fine
for some reason I can't visualize the shapefile I create even when trying by Zoom to layer. When checking the attribute table is fine. I attach here and image of the shapefile information just in case ...
7
votes
2
answers
275
views
Dissolving polygons that intersects in QGIS
I want to gather all the polygons in my shapefile that intersects with each other in several groups. If they had shared a common field I would have used the "Dissolve" tool but they don't ...
1
vote
1
answer
92
views
Applying correction value to shapefile due to older handheld GPS error in QGIS
I didn't realise that a limitation of an older handheld GPS may be that it would always be off target. After uploading polygon coordinates for a number of areas, I realised that the polygons were ...
1
vote
0
answers
29
views
Advanced digitizing not providing horizontal figures [closed]
I am using QGIS 3.16.3, working in a project EPSG:25832. After enabling a polygon layer and the advanced digitizing, when I add a feature (e.g. a rectangle), at the first click the figure is built ...
1
vote
1
answer
442
views
Converting polygons to lines and finding intersection between lines and polygons from another layer using QGIS
I am using QGIS 3.16.2 (Hannover) in windows 10.
I have three two different layers of polygons.
How do I find the intersection point between the polygons (Pink ones) and the buildings (Violet ones)?
...
0
votes
1
answer
760
views
How to set image as background for a shapefile polygon using QGIS
I would like to change the background of a polygon to an image using QGIS. Under Symbology, there is an option for Raster Fill but the .jpg image is so zoomed in you cannot see it. Is there a way to ...
5
votes
1
answer
277
views
Creating polygons with "Create shapefile layer" always produce multipolygons instead of polygons when saving in QGIS
Not sure if is a bug or I'm missing something.
Every time i'm creating a new shapefile with "Create shapefile layer" i got a multipolygon instead of a polygon (at least is what I'm expecting)...
1
vote
1
answer
355
views
Making a for loop/function testing geometries' intersections for multiple time-units in R
I have two multipolygons and I want to test intersections between their geometries based for different cycles of years.
Basically I have a flood dataset that contains flood events and their geometry ...
5
votes
1
answer
2k
views
Import CSV into polygon shapefile
I have commune level map in shapefile and CSV.
Originally, I have shapefile, exported it to CSV, then to STATA for data manipulation. Then I have exported it as CSV to import to QGIS as polygon.
I ...
2
votes
1
answer
232
views
Lost Polygons after clipping Shapefile using QGIS clip fuction
I'm trying to clip the CORINE Land Cover 10 ha Shapefile (https://gdz.bkg.bund.de/index.php/default/open-data/corine-land-cover-10-ha-clc10.html) with a district shapefile to get my investigation area....
1
vote
1
answer
109
views
Adding shapes to polygon feature in the same row
I've got somehow simple issue but cannot process it.
I am working with shapefile in QGIS (3.10 on MacOS), where having several polygon features stored as rows. I want to somehow (manually) edit some ...
1
vote
0
answers
121
views
Clipping polygons to the base map shoreline
I was given shapefile polygons that were created with ArcGIS and I when I imported them to QGIS 3.1 they are no longer clipped to the shorelines of a base map. I am hoping there is an easy way to ...
1
vote
2
answers
347
views
Shading in different parts of the same shapefile
I am creating a map of islands and I created a land shapefile using water shapefiles and therefore the land shapefile doesn't have any of the original attributes of the water shapefiles. I'm wondering ...
4
votes
2
answers
620
views
Polygons inside polygons QGIS
I am pretty new with QGIS and GIS in general.
The thing is I have 2 shapefiles, the first one with municipalities (2457 polygons) and the second one with hydrological regions (363 polygons). I need to ...
5
votes
2
answers
1k
views
Intersecting area between two polygons in the same shapefile in QGIS
I have a shapefile with two polygons in it. I would like to be able to generate the intersecting area between the two polygons.
Please note, I have tried using the intersect tool, however this does ...
2
votes
2
answers
335
views
Automatically measure polygon length in km
I have a large number (>1000) of polygons in a shapefile. I would like to measure their approximate length. The polygons are somehow elongated, so a quantity such as the length of longest line ...
3
votes
1
answer
1k
views
Calculating percent overlap between polygon shapefile and grid using QGIS
I want to calculate what percentage of each grid square is covered by part of a polygon shapefile in QGIS. So far I can get a column of whether a grid square touches the polygon or not (0 or 1), but I ...
0
votes
1
answer
79
views
Make fishnet visible but not snappable [closed]
I'm currently using a polyline fishnet grid to use as a guide when labelling land features. For example, I aim to label 10 grids per day.
An issue I have is that when creating my polygons they keep ...
1
vote
1
answer
490
views
QGIS Polygon Shapefile to PostgreSQL (PostGIS)
I am working on getting the polygon data of different areas loaded into PostgreSQL so that I can do searches within those areas based on address points.
I have downloaded postcode data from: https://...
0
votes
1
answer
57
views
Identifying zip codes that cover multiple townships
I have shapefiles with zip code tabulations in Massachusetts and township areas. Some zip codes fall completely within a single township, while some zip codes cross multiple town borders. I want to ...
-1
votes
1
answer
410
views
Clipping complete building/closed polygons only from polygon shapefile using QGIS
I have a polygon layer of buildings and a polygon layer of AOI. Now I want to clip only complete/closed polygon that falls within this AOI.
As you can see there are certain buildings that have a ...
0
votes
0
answers
34
views
combine layers in qgis
I have a Shapefile that includes country divisions (Polygon). I have another Shapfile that relates to the country's roadmap (Path). I also have another Shapfile that relates to the village points (...
2
votes
0
answers
181
views
Clip Raster by Mask Layer - Nodata output
I am trying to clip a raster around a polygon shapefile. I have managed to do it for a series of polygons with the same raster, however one polygon is returning a blank clipping with 'nodata' in each ...
2
votes
4
answers
2k
views
Convert shapefile to KML
I have one big layer which contains many polygons. This layer is a shapefile and I want to convert it to be many layers, each layer containing one polygon, and those polygon layers should be saved as ...
2
votes
1
answer
4k
views
Recover lost polygons from shapefile in QGIS
I've committed a newbie error it seems in GQIS with a polygon shapefile.
I wanted to remove about 15 of the 210 polygons, and put those 15 in another file.
I made a duplicate of the polygon ...
3
votes
1
answer
1k
views
Overlapping polygons layer order
Is there a way in QGIS to prioritize the layering order overlapping polygons. I have a shapefile with numbers in the attribute table from 1-20. Each number is associated with its own polygon. I want ...
12
votes
3
answers
7k
views
Voronoi Diagram on a given polygon using QGIS
I am trying to create a Voronoi Diagram on a specific polygon, but there is some issue when dealing with edges.
Here is how I do it:
Preparing the points for Voronoi and the polygon for the diagram
...
3
votes
4
answers
3k
views
Filtering out labels surrounding active feature in Atlas
Let me put it this way, if I’ve tried data-defined rendering and the common featureid expression and it’s still not working - and I think one or both options should - what basic thing could I be ...
2
votes
2
answers
843
views
Points to shapefile, with curved lines given center and radius (QGIS)
I'm a newbie in GIS and for a project I need to create a shapefile given some points in lat/lon. I have been following this tutorial: https://community.pyramidanalytics.com/t/q5tk8w/creating-a-...