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

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2
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0answers
11 views

Finding vectors with wrong direction in river network

I have a shapefile containing network of rivers for the whole country. The description of the layer is saying that orientation of the vector should be the same as the river flow. This is true for most ...
4
votes
1answer
81 views

How to load multiple vector layers into QGIS' map canvas using python scripting?

I am trying to write a standalone script in python to create a QGIS map canvas. The vector layers I am attempting to load are Shapefiles. Currently, I am able to load each vector layer, add them to ...
2
votes
1answer
68 views

How to convert raster (big size) to points?

I have a raster : population density of Ivory Coast. I need to convert it to points, but I met several problems because of the size I think. Here is what I tried : 1) GRASS GIS 7 command : r.to....
1
vote
1answer
29 views

Rasterize points in a map : result is not leasible. How to make the raster (points) bigger?

I have a vector layer (points) that I rasterized based on one attribute of the vector layer. I chose the GRASS GIS 7 command : v.to.rast.attribute. The raster layer appears in the map, but is not very ...
1
vote
0answers
17 views

Cropping vector map into tiles with QGIS - how to get around shapefiles which have stray points on boundary of tiles?

I am trying to use QGIS to generate a set of tiles in Shapefile format from a vector coastline map. My script is correctly generating the 5x5 degree tiles I want, however a few tiles clearly have ...
1
vote
0answers
11 views

QGIS - snapping points onto lines [duplicate]

I have two layers, one is point layer and other one is a line layer. I want the point features to snap on to the lines, but the points are away from the lines. Is there any way to move the points onto ...
1
vote
1answer
13 views

Sum habitat type within region using MapInfo?

I have two layers; one shows admin regions and the other shows habitats within those regions with columns for specific attributes and the corresponding area in hectares. I need to work out the total ...
1
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0answers
25 views

QGIS Lost precision when converting raster to vector

I am after running ordinary kriging, converting raster to vector I lose decimal value and only get whole number. I have added first the raster then the vector image.
1
vote
1answer
29 views

Using nested geometric functions in ECQL queries in GeoServer

When doing a WFS Get Feature request, I am using the cql_filter option to do some more advanced spatial filtering/quering. I am looking for the centroids of the polygons in a database that intersect ...
1
vote
1answer
36 views

Move feature(s) causes points to be duplicated in QGIS 2.8.9

I have a point shapefile in QGIS where I am manually adjusting some of the points due to overlap. I am using Toggle editing --> Move feature(s) --> Save for all layers. Instead of moving the points ...
1
vote
1answer
75 views

How do I fill a Field Combo Box with vector layer fields in QGIS?

I am new to python and I am trying to write my first plugin for QGIS. Earlier I asked this question to find out how I could populate a combobox with point vector layers (and nothing else). I've been ...
3
votes
1answer
62 views

How do I fill a combobox in QGIS with only points vector layers?

I'm new to writing plugins in python for QGIS. I've been searching on internet for a while and wrote the code below. Even though it fills my combobox, all layers (rasters, vectors of all geometry ...
3
votes
2answers
62 views

Using Buffer tool in QGIS?

I am using the Buffer tool in QGIS to put a 30 Meter buffer around a number of points. When I do this the buffer ends up taking over the entire map. enter image description here
1
vote
0answers
35 views

problem in veiwing Dxf files in Qgis

the problem of getting from DXF format, to display in QGIS correctly.we have loaded it in and fixed the rotation and TTF font mapping problems. That is all great however the objects are coming in ...
0
votes
0answers
22 views

ESRI Javascript API 3.16 with vector mbtiles file

We have a working WMTS variant with TileStrata and MapProxy, but the new mbtiles are not supported (styling incorrect). Also we have klokantech/tileserver-gl server part running now with correct ...
0
votes
0answers
29 views

Generate points layer at line intersection

I have a line layer that is actually buffer polygons converted to a line layer. I would like to generate points at all places where 3 or more lines intersect. I would settle for places where 2 or more ...
3
votes
1answer
62 views

How can I merge two adjacent polygons which borders are not touching each other

I want to merge adjacent single polygons which are apart from each other. Important note: I cannot use ArcGIS, I need to do this programatically, in any language (R, Python, Ruby, PostGIS) doesn't ...
1
vote
0answers
24 views

Missing vector features when import from .sqlite to postgis?

I imported vector data from a .sqlite file to PostGIS but not all of my vector features imported. I haven't been able to determine a reason for most of the loss of features between the databases (...
1
vote
0answers
24 views

Clipping vector polygons by previous vector polygons in same layer in QGIS

I have extremely large datasets as vector polygons in single layers. The polygons are in an order. I want the previous ordered polygons to clip the later polygons. Therefore, once an area has been ...
3
votes
1answer
35 views

List group of line segments that are not connected to any other lines

In the image below, the system of lines includes 6 segments. This connectivity gives the appearance of an "island" as the internal segments are connected to each other and are not to the outside world....
0
votes
0answers
15 views

Loading Data into Vector Layer Polygon

My first layer is a map. My second layer consists of points: bars with GPS coordinates (.cvs file). My third layer consists polygons, creating different area's for the bars. So, the points of the ...
1
vote
1answer
9 views

MapServer square symbol composed of 4 internal squares

I need to create simple square symbol composed of 4 internal squares. SYMBOL NAME 'SQUARE_TL' TYPE vector FILLED true POINTS 0 0 0 0.5 0.5 0.5 0.5 0 ...
1
vote
2answers
29 views

How to export vector file in GrassGIS to QGIS

I am using GrassGIS to analyze watershed. I created a stream vector extracted from raster elevation data, how to extract the stream vector file so I can open it using QGIS?
0
votes
0answers
29 views

Create a grid over shapefile then save each section into GeoTIFF

I have a massive shapefile with 200,000+ building polygons. I've loaded these up in ArcGIS. I need to convert this into a usable raster (GeoTIFF) that can then be tiled using MapTiler. My current ...
1
vote
1answer
16 views

QGIS, Calculate networks first, diameters second

I need to get the following task done: First, various points (stored in a shapefile, identified by a common attribute) need to be put into relation with each other (see graphical scheme, steps 1 and 2)...
1
vote
1answer
26 views

CRS and Spatial join problem

I try to match two layers. First one is point-type with cities in Europe. Second one is grid layer (polygon) with elevation value. What I want to achieve is to to join the "Z" value from grid layer to ...
2
votes
1answer
29 views

Qgis - How to count text values

My issue is to count text values from vector layer. I got a layer with streets for one of administrative region and it's names in column. It looks like this Id Street_name XYZ XYZ ABC XYZ . . . ...
4
votes
3answers
154 views

How can I make an attribute table field automatic?

I´m working in a way to make hydrologic projects using QGIS and an Excel worksheet that i have. To do this, I want to extract some information of the lines, included in a vector layer, which ...
0
votes
0answers
48 views

Prevent browser freeze when loading lots of GeoJSON features at once

In my OpenLayers 3 (v3.15.1) application, I use to load a larger amount of GeoJSON features on my map via an ol.Vector source and a custom loading fuction. This function receives the GeoJSON data from ...
0
votes
1answer
119 views

OpenLayers 3: does not display all Features of Layer

I'm using openlayers 3 and geoserver. I want to get and display a wfs layer with openlayers. this is source of my layer: vectorSource = new ol.source.Vector({ format: new ol.format....
3
votes
3answers
62 views

Projection offset between layers: OSM, GeoJSON

Don't know why there is an offset: The coordinates of the points that appear on the example were gotten through google's geocoder from some Rosario, Argentina directions. I have checked the lats and ...
0
votes
2answers
44 views

Group points and compute area

In a point vector layer, how to compute area for 4 defined ranges of values of one attribute? On the example below, I want the total area for each of the 4 colours.
0
votes
0answers
22 views

Process road polylines to not overlap building polygons

Is anyone aware of a processing tool in Grass or similar which will find segments of polylines which overlap polygons in another dataset and reroute the polyline to avoid the collision? My problem is ...
1
vote
0answers
25 views

QGIS x ArcGIS - Geoprocessing Vectors in Geographic Coordinate Systems [closed]

Is there a possibility of in future versions of QGIS, the software be able to geoprocess vectors (clip, buffer, intersection, etc.) in Geographic Coordinate System, and not only in UTM? In ArcGIS, ...
1
vote
1answer
29 views

Joining attribute data from one layer to another layer in QGIS 2.12.2-Lyon

I have a polygon vector layer that I am trying to join its attributes to a point vector layer. The problem is that the polygon layer consists of grids that are numbered 1-150 (ID) and I am trying to ...
2
votes
0answers
18 views

Trigger event after KML Layer completely loaded

I want to set the bounds of my map after a Vector (KML) Layer is loaded. kmllayer.events.register('refresh', kmllayer, function(evt) { map.zoomToExtent(kmllayer.getDataExtent()); }); In the ...
0
votes
0answers
38 views

TrueType Font Mapping for Symbols in QGIS? [duplicate]

Point object layers include Letters (fonts) that should map to a TTF symbol from the attached TTF file.I need help to setting up the TTF mappings for symbology please. I know we can create new symbol ...
0
votes
0answers
41 views

Drawing vector lines over rivers OpenLayers 3 with OpenStreetMap

I would like to know if drawing vector lines over rivers is possible with OpenLayers 3 with OpenStreetMap and if it is, how can I draw vector line of a said river. For example, I need to get a river ...
2
votes
2answers
99 views

dxf file in qgis

Please see the attached files…. The line type files load in ok however all text rotation values are lost when loaded into QGIS. This is most obvious when you load in OStext.dxf – please see grab_Mar....
0
votes
2answers
55 views

QGIS Convert vector classification map into raster

I tried to convert vector classification into raster file for accuracy analysis following these suggestions My vector data is like this: However, none works The first one, interpolation, resulting ...
3
votes
0answers
15 views

Snapping vectors to vertices for ROI delineation?

I am trying to manually extract a set of ROIs in ENVI 5.0. However, I can't seem to successfully line up the vector to be flush with the boundary of the pixels, which means I don't have fine-tune ...
1
vote
2answers
30 views

GIS data for disease vectors [closed]

Does anyone know where to find disease information in ESRI Shape vector format? I am trying to track zika, dengue, and flu in local communities, but any others are welcome too. My attempts so far are ...
3
votes
1answer
57 views

Polygon made by colour difference

I need to analyze differences (historical) in coverage of some species (seagrass Posidonia). Although its a marine species, subject area is very shallow and even from common satellite and aerial ...
0
votes
0answers
13 views

Network analysis in GRASS: dglShortestPath error: Head Node Not Found

I'm working with street networks in GRASS (v.7.0.0) and I'm trying to use the function v.net.iso and v.net.alloc based on an OSM street network with transport costs (travel times) calculated by my own....
4
votes
1answer
72 views

How to split a circle in equal parts in QGIS?

I'm looking to split a circle polygon generated by a buffer around a point in equal parts. The goal is to be able to calculate statistics about the raster that will be under the circle for each part ...
4
votes
4answers
131 views

QGIS classifying vector data

I am trying to classify a shapefile based on rule set, following this tutorial. This is the result: What I want to ask is: 1. How to insert the classification result (water, land etc) into the ...
4
votes
0answers
91 views

Import Vector data to QGIS from pdf and apply georeference

I am Using QGIS 2.14. I have a pdf created by Mapinfo, it contains multiple layers of vector data that I can open as separate vector layers in qgis. However no map projection data was saved to the pdf....
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0answers
33 views

Importing geospatial PDFs with QGIS

I've been using GDAL to work with geospatial PDFs to make geotifs and have been running into some issues, so I started working with QGIS. A fine product I might add. When I select a directory ...
0
votes
1answer
138 views

C/C++/C# Library for raster to vector conversion

I am looking for an "open source" C/C++/C# Library able to convert raster to vector data (Polygonize). I know gdal_polygonize.py is doing the job, but I can't use Python. Portrace is an other option, ...
1
vote
0answers
28 views

Command line join attributes by location using OGR

I have two overlapping vector files (polygons and sample) and want to do a spatial join from the command line to extract all features in polygons that intersect with sample. Essentially I want to have ...