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

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182 views

QGIS 2.8 Convert a vector to a raster layer

When I change a vector layer to raster using raster button->converse->Vector rasterization in QGIS2.8. I get only a black picture. Why is that so and how can I convert a vector layer to a raster ...
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1answer
29 views

How to turn a vectorgraph into raster correctly?

In QGIS2.8 version, I added several points in a point vectorgraph. When using the grid - > Conversion - > rasterized vector , The results turn out into a black figure. How to turn a vectorgraph into ...
2
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1answer
120 views

How to suppress polygon boundaries shared by objects of same type in QGIS?

Given polygons - like landcover in OpenStreetMap or street areas in cadastre - how can one suppress those polygon boundaries which are shared by objects (features) of same type in QGIS (see figure ...
3
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1answer
276 views

How to reproject all the vector files in a folder to a particular projection using ogr2ogr?

We have a folder with all sorts of vector files like tab,shp,dxf. Many of the files are in different projection. I would like to convert all the files to EPSG: 4326 and eventually the non-shapefiles ...
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1answer
160 views

How to change the style of a vector layer on a button click

Is there a way to change the style (e.g. color) of a vector layer on button click? I have defined a vector layer like this: new OpenLayers.Layer.Vector("WFS", { style: myStyle, ...
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22 views

ArcGIS Layers same coordinates not lining up [duplicate]

I have a large polygon for a borough, and smaller polygons for the local authorities within it (they divide up the borough). When I add the smaller polygon layers, the polygon appears distorted and ...
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1answer
176 views

Openlayers - Problem with selecting features from overlapping vector layers

I face the following problem. I have two vector layers. One has linestring and the other point geometry. When I add this line to my point geometry vector layer: pointLayer.setZIndex( 1001 ...
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0answers
68 views

Select feature within radius

I am developing a plugin (C++) and somehow I am stuck (I am very new to this). I start the plugin which has an own gui. There is a button to select features from the vector layer. Clicked on it, the ...
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1answer
251 views

How to make a density map from polygons/rasters (ArcGIS)

I would like to make a density map of grasslands. I have a vector layer of habitat classifications, I would like to a density map of grasslands within a specified radius. My thoughts are to: ...
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1answer
110 views

Calculating coverage of vector polygon over other polygons?

I have a shapefile file that contains a LiDAR footprint and I'm trying to figure out how much a county is covered by the LiDAR footprint. Two separate shapefiles. The attribute table for the county ...
5
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1answer
2k views

Ol3 displaying a vector layer

I have GeoJson that happily displays on GeoJson.IO that I am trying to display on a Vector Layer on an Open Layers 3 Map. The GeoJSON is in EPSG:4326, the Map is in EPSG:3857. My Code is: view = ...
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50 views

uk postcode outcode border data

I am aware of this: First character boundaries However, this only gives you the borders for, for example, 'L' rather than: L1, L10, L11, L12 etc. Can I obtain these fine grained border data from ...
2
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4answers
2k views

How to convert a vector map to raster in Qgis?

I am creating a thematic map (vector data) with different classes. How to convert this vector map to a raster map, keeping the classification?
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3answers
959 views

WFS to Vector Tiles

Is there, by some miracle, an existing piece of software which is able to convert a (3rd party, GeoServer) WFS feed into vector tiles? In a utopian world, this would happen on the fly, but a ...
2
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0answers
22 views

How to create a syntesis map ( eg. climatic vulnerability) in Qgis [duplicate]

My final goal is to create a synthesis map of climatic vulnerabilities composed by different thematic variable with different weights. I would like to ask for support for the following issues: For ...
2
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1answer
1k views

QGIS moving the layer/all features using Vector Affine Transformation

I'm using QGIS to analyse some flight tracks which were produced using a different software. Now when they are on QGIS the reference point of everything is on 0,0 which is the aerodrome reference ...
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0answers
61 views

Trying to split a complex shapefile by australian states

Im trying to work with a 1:1 mill scale shapefile of the geology of Australia. When the whole lot is loaded in to QGIS (over 200,000 polygons) it will freeze and go to slow to work with. Ideally i ...
5
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3answers
632 views

How to define layer's CRS and avoid the CRS dialog in PyQGIS?

There is an existing Shapefile, which I want to add. At the moment my code looks like: self.iface.addVectorLayer(self.shpFilePath, "Track", "ogr") It works fine, but i want to define the crs ...
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0answers
102 views

creating composite raster tiles from multiple vector layers as new background map in QGIS

I have been patiently restyling OS Vectormap product to create a map background I'm happy with, which i want to now use as a background for a leaflet map using QGIS2leaf. I understand that performace ...
2
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1answer
133 views

How to add a band with conditional value to a raster with PostGIS

I'm trying to convert a vector polygon into a raster, with pixel values that indicate the area of the intersection. I have a query that gets the area of intersection between an empty raster and the ...
1
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1answer
53 views

How to remove a parcel from a larger area?

New QGIS user here. I'm trying to clip a large (2000-ac) property boundary with a smaller (500+/-) acre property. Assuming the larger boundary is the input layer and smaller is the clip layer, my ...
1
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1answer
78 views

Is it possible to make satellite imagery viewable through a marker?

I am working on the project using Mapbox.js and jQuery and the client has asked for something that I'm not sure is possible. A screenshot of what I currently have is below. The client wants the ...
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1answer
21 views

How to add terrain information to an existing project in QGis 2.6? [closed]

I have created contour lines and a hillshade layers and saved it as a vector and as a GeoTiff file respectively. However, when I try to add these layers to an existing project, nothing shows up. Where ...
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1answer
244 views

Intersect Multiple Layers

I have thirteen polygon layers showing species at risk ranges - I have a standard arc GIS desktop license, allowing only two inputs to the intersect/union tool at one time. I need to create a "hot ...
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0answers
46 views

Downloading data after clipping

I have an issue with downloading data from GeoServer after clipping layers: 1. I can download vector layers as GeoJSON and GML, but cannot download as shape-zip: file becomes corrupted; 2. I cannot ...
18
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1answer
294 views

Is it possible to generate a boustrophedon pattern which fill a vector Region with GRASS?

Is it possible to generate a boustrophedon pattern which fill a vector Region with GRASS? I have a vector region in GRASS. And I would like to generate a vector (a polyline) being the bostrophedon ...
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2answers
96 views

Copy a Group Layer QGIS

How would I copy a group layer in QGIS? I see that you can duplicate layers but copying a layer group is much quicker. What am I missing, is there a standard way, plugin, or python code to do this?
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0answers
99 views

OpenLayers ZoomToExtent doesn´t seem to work properly with WFS layer

My website has a list of routes and a map. When I click on each route it appears its associated information and the WFS layer is selected. As a base layer I have all the routes obtained with WMS. ...
3
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1answer
291 views

D3 missing zoom Choropleth + Raster

Following this example and Choropleth from Mike's site I am trying to get: image + vector + choropleth = my map As you can see I lost the zoom capability on the vector layer. I have been trying ...
1
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1answer
620 views

Overlapping polygons in the same layer

I am working in QGIS on a vector layer where areas are classified using an attribute "typo". The problem I'm encountering is that many polygons are duplicated or overlapping, with the result that some ...
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0answers
27 views

Qgis Vector editing

i think this is a pretty simple task, but im trying since two hours and cant find a way... i have a vector made in illustrator, i want to place it exactly on a place on the openstreetmap layer (i.e. ...
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0answers
16 views

How to equally space points in a line using QGIS? [duplicate]

How do you place points in a straight line the same distance from each other in QGIS? Thanks
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0answers
51 views

Connect two contour line with calculated line lenght

Is it possible to make plugin for qgis like PEGGER for arcview 3.2? Problem is, how to make path over contour lines with a grade in percent Formula is: K= e*100/G*M ; K=10*100/0.08*10000=1.25m K- ...
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0answers
106 views

Calculating vector area in QGIS

I have calculated a viewshed (ZVI) in OpenWind and opened the raster in QGIS I have then converted the raster to a vector When I open the attribute table there are 4682 rows (features) and there is ...
0
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2answers
168 views

How to read DGN using GDAL in VB.Net?

Reading a DGN file is a big problem for me. I tried more and more but can't find a way to read a dgn(v8) file by VB.Net. After many search, i found out that GDAL can read and write dgn file, but i 'm ...
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2answers
1k views

Merging shapefile layers not working in QGIS?

How do i merge different vector layers in to one shapefile layer In QGIS version 2.6
5
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1answer
579 views

Is there a way to split polygons by several lines in QGIS?

I have a polygon (.shp) and a line (.shp) layer. I want to split the polygon in several pieces along the lines that overlap the polygon. Afterwards I want to edit each polygon separately (attribute ...
1
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0answers
338 views

Render order of vector features in OpenLayers 3

In a web map application I have a vector layer from a GeoJSON source of country borders. The layer loads perfectly and interactions such as ol.interaction.select works fine as well. I want to style ...
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0answers
115 views

How to add vector KML data in an excel table

How do I take a KML (or XML) vector map saved on my desktop showing for example a election ward and then import it into excel as a data input in a field of data. I have information in excel for ...
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0answers
142 views

Determine lat/lon intersection on earth from point in space along 3d line

I have a known point in space with a lat,lon,alt. It has a camera with a line of sight and a angle of field of view. I can take the central point and calculate each corner vector of the field of view, ...
2
votes
1answer
338 views

Loading Vector Layer using python console in qgis

I am using qgis2.6 version and new to pyQGIS. I tried to load a vector file using python console in qgis. I don't know where I am wrong. The layer was not loaded and does not show any error too. Help ...
4
votes
1answer
131 views

Comparing floor and roof areas using QGIS?

I am pretty new in this GIS topic and I would really appreciate if someone can help me with this problem. I am doing a research for university that shall show the available roof area for ...
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0answers
60 views

How to determine Affine Transformation Parameters? [duplicate]

I try to use the qgsAffine plugin to do the transformation. But no idea in its usage. Anyone can post an example. Many thanks!! How to find the transformation parameters? I found some posts suggest ...
2
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0answers
24 views

Help getting a Mathematical Representation within a Layer's Attribute Table

I'v been playing around with Vector Coding and was wondering if there was any Plugins out there that might let me represent Vectors within a layer as it's Mathematic attributes in the Layer's ...
1
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1answer
456 views

What is a memory vector layer in QGIS?

What is a memory vector layer and how does it relate to the vector layer? Background info: I have a volunteer working with my organization, because of financial reasons we have him using QGIS. He ...
2
votes
0answers
30 views

Aggregate nearby points to develop equally sized regions in QGIS

I have a list of 4,500 points (lat, long, unique id, attribute). I also have a service territory which all of the points fall into. I would like to break the service territory (polygon) into 6 ...
3
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3answers
169 views

Plotting Geo Points with “by arc centered at” Instructions

A recent Supreme Court decision redefined the legal boundaries of California along the Pacific Ocean: http://www.theverge.com/tldr/2014/12/15/7397085/supreme-court-california-boundaries-map I am ...
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0answers
24 views

When trying to save a vector in QGIS a blank dropdown window appears

I am learning and using QGIS Brighton and have hit a obstacle. Everything has been going fine until I started using the experimental generalizer to smooth the contours that I had extracted from some ...
1
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1answer
151 views

Raster map & vector boundaryline data for Istanbul, Turkey

I'm looking where I can download background raster map for Istanbul (street map?), and then a boundary line file of the the 39 Districts in Istanbul. Does anyone have any recommendations?
3
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1answer
865 views

How to cache and server pre-rendered vector tiles in pbf format?

I want to serve vector tiles server in pbf format. For that I used Mapnik-vector-tiles which is bundled by avecado. Using avecado_server i can render pbf tiles on the fly using ./avecado_server ...