Questions tagged [vector]

A coordinate-based data model that represents geographic features as points, lines, and polygons.

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14 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 ...
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1answer
41 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 ...
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1answer
73 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 ...
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1answer
35 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 ...
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0answers
17 views

Edge detection to vector [closed]

How to Result Edge Detection, which is raster and has only one band convert to vector in google earth engine. I did the edge detection, and now I want to convert that result into a vector. How can I ...
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11 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.
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2answers
46 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 ...
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1answer
22 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/...
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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
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3answers
65 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
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1answer
44 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 ...
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11 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 ...
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35 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
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1answer
40 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 ...
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0answers
18 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 ...
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1answer
94 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 ...
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1answer
21 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
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1answer
41 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 ...
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0answers
32 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, '...
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1answer
33 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 ...
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0answers
22 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 ...
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0answers
16 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
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1answer
29 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: ...
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2answers
43 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 ...
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0answers
21 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
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1answer
69 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 ...
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0answers
36 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 ...
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0answers
18 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 ...
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0answers
44 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 :...
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29 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=...
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1answer
90 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. ...
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22 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 ...
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1answer
69 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 ...
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1answer
32 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
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1answer
25 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?
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0answers
35 views

Vector tile generation

I have a full planet imported in PostgreSQL with imposm3. What is the best way to generate vector tiles (MVT in .mbtiles) from PBF/PostgreSQL with maximum hardware utilization (distributed generation ...
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2answers
139 views

Creating building shadows in QGIS?

Can anyone think of a simple way to create a polygon to represent building shadows? I have a shapefile with height information for the buildings and I want to create a simple plan looking like the ...
5
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2answers
120 views

Splitting polygon using another polygon in QGIS?

I have two polygon layers (yellow and orange in the attached image). I am wondering if there is a way to get a count of the number of isolated areas that the orange polygon has divided the yellow ...
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2answers
91 views

Problem with intersecting lines over a polygon layer in QGIS

I have a shapefile with lines (a road network) and I want to intersect it over a polygon layer in order to finally have a polygon layer (each cell has an ID number) with the intersected lines for each ...
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0answers
230 views

Converting vector in NED to ECEF? [closed]

I have a geodetic WGS84 position, lat, lon, alt, and direction cosines from the same point, uN, uE, uD. I'm brand new to geodetic/ecef conventions. How do I take a vector (say, a unit vector with ...
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1answer
46 views

Python: Convert shapefile to GeoJSON whilst stripping and renaming fields

I'm writing a Python script to convert shapefiles into GeoJSONs but I would like to remove many of the fields as they are redundant and rename the ones I am retaining. Here's an extract of where I ...
2
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1answer
87 views

3-D Terrain effects for vectors in QGIS?

I'm a bit new to QGIS, and making a few maps of roads through mountains. I'm looking to have a 3-D effect within my 2-D map. I got a DEM, made a hillshade, and blended a basemap over it. Nice ...
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2answers
41 views

Reclassifying vector polygons based on text string to integer using Python Parser of ArcGIS Field Calculator?

So I am trying to reclassify a text string by searching for bits of strings and converting those strings to an integer value in a new field within the field calculator. e.g. I want to find all values ...
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1answer
47 views

Calculating areas of polygons that match with overlapping raster threshold value?

I have a polygon of districts (districts.shp) and a raster of rainfall (rainfall.tiff). I want to calculate the area of each district that saw rainfall greater than various numbers. I'd like to ...
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0answers
24 views

Can only select certain polygons

I have only one vector layer on my map, and it's not letting me select some polygons. For instance, this is what happens when I try to select a certain polygon (the yellow outline with the blue star ...
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1answer
54 views

Map based on highest percentage from different variables

I've the 8 social classes (see under) for +- 900 polygons. I would like to create a new column that keep only name of the main social class for each row (based on the percentage). After that I would ...
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2answers
72 views

Seeking tool to work out overlap between two polygon layers and their statistics using QGIS

I have two polygons in QGIS. One is a land-use map, which polygons that include different types (forest, agriculture, urban etc). I also have a vector polygon that represents a flood extent. I want to ...
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0answers
71 views

Fixed distance buffer is oval in QGIS?

I want to create circles of diameter 20m in QGIS. I create a point and then use vector - geoprocessing tools - fixed distance buffer. My problem is that the size is crazy and worse, the shape is not a ...
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0answers
44 views

Computing Moran's I for vector data in GRASS

Does GRASS allow for computing Auto-Correlation using Moran's I statistic from vector files. GeoDa and ArcGis can do this. But seems grass lacks this functionality https://grass.osgeo.org/grass76/...
3
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1answer
64 views

Fixing self-connect polygon in QGIS 3.2

I'm trying to clip a soil map layer and am getting invalid geometry that affects my clip result. The problem appears to be a self-intersecting polygon. I've tried using the 'check geometries', and ...