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

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3
votes
1answer
41 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
23 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 ...
0
votes
0answers
14 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
8 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
15 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 ...
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
28 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
140 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
37 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
81 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 ...
3
votes
3answers
55 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
36 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
21 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
26 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
17 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
26 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
77 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 ...
0
votes
2answers
48 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
13 views

How to snap 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
29 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
55 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
10 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 ...
4
votes
1answer
65 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
124 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
80 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 ...
3
votes
2answers
97 views

How to remove parts of raster layer with QGIS (equivalent of difference tool but for raster)?

I'm trying to get the difference between two raster layers the same way we can do it with the difference tool with vector layers. I'm using QGIS 2.14. Anyone has already done that and can tell me how ...
1
vote
0answers
30 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
92 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
26 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 ...
0
votes
1answer
33 views

Combining overlapping polygons to make a raster

I'm working in Arcmap10.3. I have some polygons layers that over lap that I want to merge to one polygon layer. Then I want to convert it to a raster in the end. I want the top layer of the 4 input ...
3
votes
2answers
50 views

Cannot load vectorlayer PyQgis

I am having a hard time loading a vectorlayer from the console. Not from the Pythonconsole within QGIS, but from the console on my computer. I later want to write a standalone script! That is what I ...
3
votes
1answer
45 views

Land use change detection with large amount of vector files

Im doing a project where I'm creating a map that shows how land use changed from 1990-2000 for the city of Minneapolis. I have three files, one of the cities boundaries, one with the land use of the ...
2
votes
2answers
57 views

R use data in SpatialGrid to create SpatialPoints

I am trying to make a grid of points to overlay on a raster of vegetation of Kansas, U.S.A. My idea is to use the points as a sort of centroid for the raster pixels, which are 30m resolution. When I ...
5
votes
1answer
59 views

QGIS Vector Toolbar Has No Tools

I am trying to use the Table Manager to rename a field in an attribute table. However, the Vector Toolbar in my install of QGIS 2.14.0-Essen 64-bit Windows shows a toolbar with no tools in it. The ...
2
votes
1answer
43 views

Converting an ENVI raster as point shapefile for editing in ArcGIS?

I have an ENVI raster with multiple classes inside. I tried to export this to a vector so that I can convert it to a shapefile in ArcGis (I want to manually edit/delete points in the raster), but the ...
2
votes
0answers
31 views

Converting u and v from WGS84 to NZTM2000 - Do I need to do vector conversion?

I have u and v wind component values in latitude and longitude in WGS84. I want to convert this to NZTM2000. I've converted the lat/lon in ArcView - (and will try in R) - but do I need to also do some ...
1
vote
1answer
83 views

Import vector PDF into MapInfo

Is it possible to import a PDF with vector layers into MapInfo as vector layers? If yes, how would I go about doing this?
0
votes
0answers
14 views

How to decide a which server is best for geo-spatial data servicing? [duplicate]

I want to serve both vector and raster data sets of large volume (ex: for a country). Right now I'm using GeoServer for vector and MapServer for raster. Is there any literature or reference such ...
4
votes
1answer
98 views

QGIS Composer Distorted SVG PDF Output

I've noticed that some SVGs are distorted when outputting to a vector PDF from QGIS. A good example is NorthArrow_07.svg. The image on the left is how it looks in the composer and the image on the ...
0
votes
0answers
30 views

Incomplete/incorrect extraction of raster values from shapefile in R

I am having trouble correctly extracting raster data from all the polygons from a given shapefile in R. The raster and shapefile have identical CRS in QGIS (EPSG:32654, WGS84 / UTM zone 54N). After ...
2
votes
0answers
22 views

QGIS upgrade from 1.8 to 2.12: Vector layers are not displayed

I just updated my very outdated version of QGIS. I was running 1.8 and thought the new version would work out a couple kinks that had developed. Well, now I can't even figure out how to make my vector ...
2
votes
0answers
56 views

QGIS becomes unresponsive when adding new vector layers?

QGIS suddenly won't allow addition of new vector layers when running on PC (Lyon 2.12.1). I've reinstalled it, no help. I've recently changed to Windows 10 from 7, otherwise nothing much has changed ...
1
vote
0answers
31 views

How to get a multi-attributes vector from an SRTM raster in QGIS?

I split an SRTM raster into 3 different raster files representing the altitude, the slope and the exposure, using QGIS DEM analysis tools. How can I output a single vector file with the 3 attributes ...
3
votes
2answers
57 views

How to make a line shapefile converted from a gpx track file display over basemaps such as OpenStreetMap?

I have created a line shapefile from a Garmin gpx track file using QGIS 1.12.3 Lyon. Resultant vector file displays properly with other vector shapefiles. Problem is that created vector file (line ...