Questions tagged [vector]
A coordinate-based data model that represents geographic features as points, lines, and polygons.
1,367
questions
1
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1answer
45 views
How do I find the area of a polygon covered by points of a defined size? (QGIS 2.18)
I'm using point vectors to portray 264 marked trees in a stand using the 'Random points inside polygons' tool (it doesn't matter where they are). Each point is 4.5m across (the average single tree ...
3
votes
1answer
41 views
Split vector layer in R
Is there a way to replicate the Split Vector Layer function from QGIS in R?
I have a Shapefile containing around 20 polygons that I'd like to split into 20 separate files.
I guess since it's in ...
0
votes
0answers
25 views
GeoServer not exporting polygon to PDF [closed]
We've got an issue where we're working with two layers - raster and vector, trying to export from GeoServer to a PDF however the vector keeps overlaying on top of the raster rather than showing it ...
2
votes
1answer
23 views
Select raster tiles within vector polygons
I have a shapefile with polygons of all the countries of the world. I also have a raster .tiff (250m square pixels) of average wind speed per pixel.
I want to select all the tiles which lie within ...
1
vote
1answer
39 views
Selecting Matching Features in shapefile [closed]
I have a shapefile that draws up all 200 districts in a country. I want to select and colour 100 of these that I have on my list.
What would be the simplest way of going about this rather than me ...
0
votes
0answers
23 views
How to add a vector layers to my map using OpenLayers 3?
I'm trying to add a vector layer manually to my map but i receive this error: Uncaught TypeError: b.attachEvent is not a function
the code is :
// adding data
// Define Geometries
var point = new ...
0
votes
1answer
20 views
Treetop location in 3D: How can I find the coordinates (x,y,z) of point cloud's local maxima within polygon vectors?
I'm doing forestry analysis of some point cloud data and I have used segmentation procedures (i.e. watershed algorithm, etc..) to delineate the crown boundaries of individual trees in 2D.
The vector ...
0
votes
0answers
26 views
Adding vector layers to map using OpenLayers?
I'm trying to add a vector layer manually to my map using OpenLayers 3 but I receive this error:
Uncaught TypeError: b.attachEvent is not a function
The code is :
// adding data
// Define ...
0
votes
1answer
46 views
How to make sure that vector and raster data align correctly in ArcGIS?
I have a shapefile of European states (open-access from here: http://tapiquen-sig.jimdo.com) and DEM data downloaded from Copernicus.
Europe states vector is in GCS_WGS_1984
(Datum: D_WGS_1984,
...
1
vote
1answer
34 views
How to get pure base topo map without any human made things?
I need detailed world map (preferably vector), just like Google Maps Terrain, but without roads, streets, airports etc. Just pure base map like an atlas with mountains, deserts, rivers, lakes etc. ...
2
votes
1answer
48 views
QGIS Measure Distance Using Field Calculator
I have a point shapefile with 80K+ records. Shapefile is projected in wgs84. The shapefile contains fields with the latitude and longitude of the point. I need a new field that contains a distance ...
1
vote
1answer
33 views
Creating gradient-filled rectangle in PyQGIS layout?
I have created a print layout with some of the layers of my QGIS Project using PyQGIS. I am trying to add a gradient filled rectangle to the layout. In the GUI, I would use the "Add Shape" --> "Add ...
0
votes
0answers
34 views
rasterio rasterize does not take geometry
rasterize(allshapes) return;
"ValueError: No valid geometry objects found for rasterize"
Testung a single shape:
print(shape.GetGeomFieldRef(0))
POINT (56.91288 27.33519)
print(is_valid_geom(...
1
vote
1answer
36 views
QGIS Raster to Vector Conversion - 3.4.6-Madeira
I have some contour lines in raster format, I want to convert them vector. I tried with QGIS (version 3.4.6) I got the vector form.
But when I tried to select the contour lines to put the actual ...
-1
votes
1answer
31 views
Seeking polygons that map out land zone type (ie Residential, Industrial, Commercial) in UK?
I'm looking at displaying the commercial and industrial areas of the UK on QGIS so that I can do some work on them. I'm not looking to add my own data to it, merely find a shapefile or geopackage or ...
0
votes
0answers
13 views
Vector transformation and Vector Bender-Reg
In addition to Spatial shifting of Point feature using Vector Bender-Reg which I asked yesterday, I found anther plugin in QGIS called "Vector Transformation"
IN QGIS another plugin "Vector ...
2
votes
0answers
45 views
Spatial distribution of vector polygons
I have two vector layers and I am looking for a tool for spatial distribution of the polygons. polygon 1 is the frame, polygon 2 are objects with different size and distribution. I need an index value ...
1
vote
1answer
54 views
QGIS 3.4 Rule Based Symbology - Exact Matches Integers in String e.g. 2,12 + 1,2,3,12
I have a shapefile containing a String Type Field called 'Class'. This field contains one or more integers separated by commas.
I want to create Rule-Based symbology matching only 2, 12, 1 ...
3
votes
1answer
99 views
Calculating real length and slope of roads
I have collected points alongside road in form of csv files with z-values. When imported in QGIS I used Set Z value and Points to path to make line. When I use right button in Identify Features tool I ...
2
votes
1answer
42 views
Shapefile to polygon, then edit the polygon in order to use it as a mold
I am working on QGIS with a shapefile:
I transform it through Raster-> Conversion-> Polygonize
Then I eliminate some parts (Sea), and those that are bigger than one single square of grid but are ...
1
vote
0answers
13 views
How to plot Geoserver data (point data) as image on the map instead of vector plot? [closed]
Need the help to integrate it with angular 5 if possible.
2
votes
2answers
54 views
Summing Area of polygons within vector layer within zone using QGIS?
I have one vector layer with multiple polygons (purple). I also have a number of other vector layers which are catchment zones (I also have a layer where these catchments are merged).
Is there any ...
1
vote
1answer
35 views
Selecting a polygon area in a raster image - rasterio.mask vs roipoly
How should I select a polygon area in a raster image?
So far, I have seen two methods:
use a vector mask or a shapefile (some examples here: http://www2.geog.ucl.ac.uk/~plewis/geogg122-2011-12/...
1
vote
0answers
16 views
Running v.net.steiner in segments?
I am using GRASS GIS 7.6 on a CentOS server with 157 GB of RAM. The vector categories of the network layer that I need to run the Steiner tree algorithm on are as follows:
Layer/table: 1/network
type ...
4
votes
3answers
68 views
Counting number of polygons inside zone using QGIS?
I've seen a lot of questions about counting the number of points within a polygon but my question is I have 1 vector layer with polygons showing past landslides that have occurred and another 206 ...
2
votes
1answer
56 views
Error converting vector shapefile to raster (.TIF) in QGIS?
I am working with a shapefile of 10km grid regions of the UK obtained from digimap.
I need to convert this to a raster in order to do some analysis in R regarding agricultural intensity of 10km UK ...
1
vote
0answers
17 views
Interactive tool for editing TIN data
I created TIN to generate DTM using Mass points from Lidar data and river data that I made from stereoplotting. TIN results show there are several locations where the river elevation floats. So I have ...
1
vote
1answer
59 views
QGIS freezes when trying to view layer properties
As of recently whenever I try to edit the properties of a vector layer the entire program just freezes and I'm forced to end the process using task manager. I use Windows 10. Any reasons as to why ...
3
votes
1answer
43 views
Creating DEM Contour files from shapefile line data in QGIS
There are many question occurring on this forum regarding this issue, however the issue I am facing has not been answered in Generating DEM from contour Shapefile using QGIS?, which is that I have ...
0
votes
0answers
19 views
Identifying Optimal Site Locations with Variables Weighted By Level of Importance
I'm using QGIS 3.4. I have a point shapefile representing population density, and I have used the "K means" vector tool to identify the 12 most optimal locations for service centers that would serve ...
1
vote
1answer
107 views
Replacing multiple polygon features by their shared center point in GRASS GIS
I have three polygon features of the same category in a larger vector layer from which I would like to create a center point (mean coordinate) that holds the same attributes as the three polygons.
I ...
1
vote
1answer
22 views
Intersection of raster and vector - road file and maps (tif)
ArcGIS Desktop 10.6.1
I have a railroad vector layer (with 10 rows, that is 10 segments) and 30 USGS historic maps (tif files) that cover that route. I'd like to find the intersection, such that one ...
2
votes
1answer
47 views
Coordinates of an area on a raster in QGIS
I am new to GIS and I have to do the following:
I have a GeoTIFF raster file of a map with some features like clouds and water bodies. It is a satellite image. My images are taken from a snapshot of ...
1
vote
0answers
34 views
QGIS: Polygonize error
Running the Polygonize tool in QGIS keeps generating the following error:
Processing algorithm…
Algorithm 'Polygonize (raster to vector)' starting…
Input parameters:
{ 'BAND' : 1, '...
1
vote
1answer
40 views
Polygonize specific raster values QGIS
I have a raster of 36 classes of the land cover in South Africa. However, I only need 4 of these classes and create a polygon out of these 4 classes combined. I have now used the raster calculator to ...
2
votes
0answers
23 views
Query of line direction histogram plugin
I was wondering if anyone could explain how this plugin works I have had a play around with it and I do like how it visualizes how vectors are orientated. However I ran one and opened the CSV file ...
1
vote
0answers
17 views
Calculating the distance of raster cells from a vector within a polygon using QGIS
I am quite new to QGIS and am trying to use QGIS 3.6 to create a raster layer of calculated values of the minimum distance of each cells within a polygon (orange) from a vector (the river channel in ...
2
votes
1answer
30 views
Store results including style in vector format for QGIS, ArcGIS [closed]
As I am wrapping up my project, I would like to make my results available for download. There are however many flavors to choose from and I was wondering what format is best.
My criteria include:
...
1
vote
2answers
50 views
Clipping raster by mask layer with rule that it only clips raster if shapefile overlaps by 10% using QGIS?
I am using QGIS.
Is it possible to clip a raster when the shapefile overlaps with it by 10%?
Clip raster by mask layer tool is fine for Ontario (left) but makes me lose a lot of data from smaller ...
2
votes
0answers
24 views
How to delete a file after processing an algorithm in QGIS 2.18?
I am trying to delete an intermediate file ("Temp_merged.shp") after running the singleparts to multiparts algorithm in QGIS 2.18.
import glob, os, processing
path_to_shp = "C:/Temp/Tracks/"
...
3
votes
1answer
73 views
Merging all vector files within directory with QGIS?
I am unsuccessfully trying to merge all shapefiles in a given directory using QGIS 2.18. I do not want to navigate to the folder using QGIS GUI tools. Instead, I want my script to include all ...
2
votes
0answers
48 views
Vector map (rivers) to Raster. [ **ERROR 1: Wrong value for -outsize parameter.**]
I want to transform this vector map:
To something like this
I only tried to convert the vector map through Raster> Conversion> Rasterize
But I get this Error:
QGIS version: 3.6.3-Noosa
QGIS code ...
1
vote
0answers
19 views
Can QGIS be used to calculate the up-slopes (total area draining to a specified point) of multiple separate points simultaneously?
I am trying to calculate the area draining to a point of 240 separate points using QGIS. At the moment I'm using the Saga - Upslope Area algorithm to individually work this out for each of the 240 ...
2
votes
0answers
45 views
Isolating main polyline using QGIS?
I am trying to convert a line shapefile with branches into just one polyline, actually deleting every other diramation.
Imagine something like this:
:________|__________|____|||______
into
:...
0
votes
1answer
44 views
Clipping by mask results in blank output
After clipping by mask in QGIS 3.6 the output file has been blank (empty). Raster file and vector mask file have the same projected CRS:
USER:100029 - * Generated CRS (+proj=igh +a=6370997 +b=...
2
votes
1answer
94 views
Retrieving lines radiating from point with v.select in GRASS GIS 7.6
I am attempting to select lines that radiate from a point using v.select in GRASS GIS 7.6 (also tested with 7.4.4) in Windows 10.
I start out with 48 lines radiating from a point every 7.5 degrees. ...
0
votes
0answers
28 views
Loading layer with QgsVectorLayer in standalone PyQgis 3
I can't seem to figure out why my layer won't charge in QGIS.
After reading many topics, it seems to be linked to the prefix path. However changing this, does not seem to work (I tried around 10 ...
1
vote
1answer
83 views
Automatic correction of many topological errors in shapefile?
I have a database with topological error. In particular I have an overlay of polygons. I would like to correct these errors.
I thought to use an automatic procedure since I have a lot of errors. I ...
0
votes
1answer
39 views
Correcting topological errors in QGIS?
Using the topological corrector inside Qgis I have identified overlapping polygons. My situation is represented into this image
My polygon of interest is located below another polygon (the red ...
1
vote
1answer
32 views
Is there an alternative function which does the same thing as clip raster by masked layer on QGIS?
I am having some technical problems with the clip raster by masked layer and I faintly remember using a different method a long time ago for a similar problem. Anybody familiar with another function?
