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

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9 views

Problem in Style [on hold]

How we can give style according to the attribute table. In the image attached i want to style the layer according to text attribute. that is 'n' should be in one style and other character should be ...
1
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1answer
13 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
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1answer
24 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
27 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
119 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 ...
-1
votes
0answers
12 views

Want to show % on a province map [duplicate]

Note : I want to show the percentage of Permanent Resident cards issued in different Category ( family class, refugee , etc) by the Canadian government on a province map . Basically, I want to ...
0
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0answers
24 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
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0answers
49 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
39 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
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2answers
35 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.
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0answers
19 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
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0answers
24 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
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1answer
18 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
11 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
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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
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0answers
20 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
70 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 ...
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2answers
43 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
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0answers
12 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
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2answers
27 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
51 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
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0answers
8 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
60 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
112 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
60 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
86 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
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0answers
25 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
60 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
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0answers
22 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
31 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
43 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
55 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
54 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
38 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
29 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
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1answer
61 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
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0answers
13 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
92 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
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0answers
29 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
21 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
55 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
26 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
56 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 ...
2
votes
1answer
67 views

QGIS - PYQGIS Import gpx as vector layer

I'm trying to use the python console to import some gpx files as vector layers. When I do it manually I have to choose which layers to add, my options are: I've tried various versions of the code ...
2
votes
2answers
136 views

How to label one point bigger than all others in a layer?

I have a point dataset in one layer. I labelled all points but I would like to label one point larger size than other point labels. How can I do it? Merzifon and Bahçecik are in the same point ...
3
votes
0answers
28 views

zonal statistics / join with two vector layers [duplicate]

I have a shapefile containing three polygons of river basins with different values. I want to know the average values per country. The country thus contains three river basins. When I use join in ...
5
votes
1answer
73 views

Aggregating polygons with space between them

Im currently editing a large dataset that has large chunks removed throughout (buffered road network). The areas adjacent from each side have coinciding attributes, but have this large erased area in ...
1
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0answers
33 views

save shape file as grouped/layered vector file

I want to get the 10m natural earth countries file into a mercator projection and then into a vector file (svg, ai, etc) where for each country, its main land and any of its islands are in a single ...
2
votes
0answers
63 views

QGIS 2.12.3 Crashes on buffering line vectors

I'm using QGIS 2.12.3 and I'm trying to create a buffer of 100 mt around a line vector using the Vector - Geoprocessing Buffer tool, but qgis crashes at every try. I've already checked that the RS of ...