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

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3answers
35 views

Checking for proper administrative location?

I have two vector layers. The first layer contains points. This layer has a lot of fields with data like name of district, voivodeship etc. The second layer (polygon) is showing administrative ...
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0answers
337 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 ...
1
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2answers
82 views

Splitting raster in QGIS? without cliper

I have polygon grid layer and raster image whitch want to split with my grid layer to have 9 new raster layers. I was doing it like this guy but my QGIS stop working and shut down every time when I ...
1
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1answer
148 views

Cannot get Openlayers 3 WFS vector layer from Geoserver

I read a book about Openlayers 3 and I guess its about an older Openlayers version because it mentions a ol.source.ServerVector vector source for getting WFS layers from a server. In the latest ...
1
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0answers
29 views

Distance Analysis from single point to multiple points on vector layers

Is it possible to do the following in QGIS: Create a text file that plots the distance from a single point (stored in one layer) and multiple points (stored in another layer). I have tried to use ...
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2answers
28 views

QGIS: Class boundaries

I have seen that people already had issues about overlapping class boundaries with the classification of graduated vector data. I am wondering if there is somewhere written in the documentation if ...
2
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2answers
85 views

Convert point to line

A little background: I recently completed a long bike trip and used a GPS to gather data during the ride, including average speed and elevation loss/gain. I imported the data into QGIS. These data ...
5
votes
1answer
133 views

Create shapefile of raster outline using python

I want to create a single bounding shapefile polygon of valid pixels in raster data (GeoTIFF) using python. I need something efficient as I need to do this for hundreds of rasters. I had thought of ...
1
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2answers
89 views

Selecting Specific Elevation Areas Contiguous to the Coastline for Coastal Flood Mapping

This is less a problem than an inquiry into a better way of doing something. I am curious how people might go about selecting, say, all areas less than or equal to 10 feet (from a DEM) that are ...
1
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0answers
52 views

Alternatives to QGIS difference tool

I have a very large shapefile of building polygons and a shapefile of the country they reside in (England). The building shapefile was built by merging 94 smaller shapefiles. Both files have the same ...
1
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1answer
124 views

QGIS elevation and relief shade

I am trying to generate a map with terrain and elevation in QGIS and as a beginner I have followed tutorials on how to generate contours and hill shades succesfully. However, I don't know what are the ...
2
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1answer
42 views

Most recent tectonic plate data

What is the latest update to the positions of the tectonic plates? Does anyone have a most up-to-date shapefile or vector of the tectonic plates?
5
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0answers
279 views

QGIS: How to reverse vertex ordering in polygons

I am working with an Oracle spatial connection in QGIS through which I am accessing and editing a vector layer. I find that when I edit a geometry, the vertex ordering is reversed (to clockwise in the ...
2
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1answer
328 views

QGIS field calculator expression: selecting min/max values within field groups

I am new to using QGIS (previously used Arc) and trying to get my head round the expressions and Python. I have series of polylines representing routes and require the linear distance from the ...
6
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5answers
7k views

Merge overlapping lines in ArcGIS

I have a polyline shapefile containing a number of lines, some of which overlap. By overlap, I mean that they follow exactly the same path for some of their route, but also have bits that are not ...
0
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1answer
51 views

how do i create OGRSpatialReference from raster file's georeference C++

I want to create .shp file using ogr with georeference based on my raster file, so i create an ogr layer using CreateLayer( "point_out", NULL, wkbPoint, NULL ); i want to set the OGRSpatialReference ...
1
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0answers
75 views

Clipping polygon using QGIS?

I want to clip a polygon using Qgis "clip" tool. The problem is that the resulting polygon presents areas that where not clipped off. The first screenshot shows the layer I want to clip using the ...
1
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1answer
289 views

ArcGIS feature class interprets Latitude/Longitude in meters instead of degress

I wanted to tie toegther some data from my database table to an ArcGis map. The table contained an Object_Id, GIS_LATITUDE and GIS_LONGITUDE column. I added the feature layer based on the table (x as ...
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0answers
24 views

Plunge and trend of vector lines in ArcGIS for Desktop?

Does anyone know how to extract dip and dip-direction (or trend and plunge; dip and dip direction define the spatial orientation of planes, trend and plunge of linear elements) data from a series of ...
2
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1answer
374 views

How to edit a vector layer extent?

I'm working on QGIS 2.2, and I would like to make a vector layer extent bigger (thus the clip option is not suitable) to match exactly my mask layer extent. I would like the new added area to be ...
5
votes
1answer
241 views

Convert Graphics to Vector in QGIS

I am wondering if there is a way to convert a graphic produced from symbology in QGIS to a vector layer (ie: shapefile). I have a point layer with bearing direction in the attribute table. Following ...
5
votes
1answer
399 views

How to compare two sets of points in QGIS?

I have two point layers with XYZ data; one set are points measured in the field and the second set is a Lidar data set. I want to check the accuracy of the Lidar in comparison to the measured data. ...
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0answers
57 views

How do I create a map of addresses?

This is a tricky one. A little context first: Bentiu wiki page: https://en.wikipedia.org/wiki/Bentiu + OSM map of Bentiu refugee camp, South Sudan: http://www.openstreetmap.org/#map=16/9.3314/29.7920 ...
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1answer
50 views

Creating Polygon from a Raster

I have a Raster representing climate data. I converted the raster to vector using the tool raster to vector (Arc Map) and i got something like below: Can somebody help me out by guiding me in actual ...
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1answer
91 views

How to merge vector buildings height layer with raster DEM to get solar maps in r.sun in Grass GIS?

Welcome, this is my first post. I have vector layer with buildings heights and vector/raster DEM file. I need to create solar maps with sun radiance values on the roof (and on surface, ofc). I am ...
0
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1answer
82 views

Is QGIS Server working like this?

On CentOS 7 I have QGIS Server and QGIS Desktop installed. In QGIS Desktop I created a project with raster and vector data and saved it in a ".qgs" file. Then I copied the file in ...
2
votes
2answers
73 views

How to split a vector file by date (year) but the column containing dates is in Day/Month/Year format.

I am using national accident data in QGIS and quite frankly the dataset is huge as it contains every recorded accident between 2005 and 2014. I've split datasets by field for a number of vector ...
3
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1answer
108 views

Is the QGIS “Random selection within subset” selecting spatially random or randomly from the attribute table?

I am trying to figure out exactly what is being randomly selected. I have a layer of road segments and I would like it to select a road segment at random within a neighborhood (the subset). This would ...
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0answers
27 views

Polygon to multiline object in ArcMap/ArcGIS Pro

Is there a possibility to create a multiline object from polygon object contours in ArcMap? I found that Edit toolbar allows to create polygons from other shapes, but I couldn't find anywhere an ...
3
votes
1answer
57 views

Why is QGIS only one label rendering at a time?

I'm new to QGIS, but I'm experiencing what I think is a bug. When I load the qgis_sample_data landcover raster and lakes vector layers, then enable labels for NAMES on that layer, I can only ever ...
2
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1answer
152 views

Shapefile/vector layer not appearing in QGIS

I have a shapefile (calling it 'new.shp' for discussion's sake) that won't show up with other layers. If a fresh file is started and I bring in new.shp, it will appear, but any other layers imported ...
1
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1answer
36 views

Query across layers of SHP files?

I would like to query features from a SHP vector that intersect with features from another vector. Pseudocode: "Name" IS intersects( countries) How would be the valid query composed?
0
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0answers
95 views

3D building data for London

Any tips on where I can find 3D building data for UK/London, preferably LOD2 (Including roof structures)? I am aware of the Virtual London dataset but I would like a more recent one.
1
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1answer
136 views

How to get a “clean” polygon after using dissolve in QGIS?

I'm trying to obtain the boundaries of shapefile, thus to clean the inside as a matter of speaking. While I had expected that dissolve while get me a proper polygon, unfortunately it still has some ...
1
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1answer
58 views

reading GRASS vector map in python

I know similar questions have been asked several times, but none of the solutions seems suitable for my problem or don't work.. I computed flowlines using the r.flow tool from GRASS GIS, then I ...
11
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8answers
10k views

How to georeference a vector layer with control points?

I have a non-georeferenced vector layer that I need to be georeferenced. With raster layers the task is easy and straightforward, but I have no idea what should I do with my vector layer. I have a few ...
0
votes
2answers
104 views

QGIS 2.10, csv points to vector grid

I have a series of point data from a .csv file that I would like to display as a heatmap raster, the .csv data have various attributes with them and I would like to adjust the color ramp based on ...
4
votes
3answers
1k views

How to change layer transparency without changing border lines?

I have a raster image of elevations. I have added a vector shapefile that contains local political divisions. I want to keep the elevation colors, but I want to keep the black lines representing the ...
1
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2answers
146 views

Free 3rd party library for showing geospatial vector information

Up to now, I have used GDAL to extract raster data from geotiffs and then, OpenGL to show that raster data. But when it comes to extract vector data with the help of OGR, what library would you ...
2
votes
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?
1
vote
1answer
70 views

Retrieve MapBox tiles in vector format rather than raster

I am using MapBox and I would like to render my tiles directly from vector format but I was not able to find how to retrieve the tiles in vector format rather than bitmap. So, when I use this url: ...
2
votes
1answer
56 views

Extracting area from DEM Raster?

After applying constraints to the DEM I polygonised the raster (using GRASS r.to.vect.area) The result is shown below with a lot of vector with resolution = [30 * 30] Is there any solution to make ...
0
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0answers
7 views

Sky View Factor of building roofs => Vector algorithm [duplicate]

I'm currently working on a project in which I'm trying to assess the SkyViewFactor of a given roof using building vector data. I've already managed to build a process based on vector rasterization ...
1
vote
1answer
67 views

QGIS Vector Data with blank attribute tables

I have vector data shapefiles for Manitoba, but there is no names in the attribute tables. It seems Manitoba is still working on their attribute data. Is there a shapefile I can download to get these ...
2
votes
0answers
86 views

How to tell if map service is fully vector or raster?

sorry if this is a duplicate, but I was wondering how to tell if a map service (in web browser) is vector based or raster based? What I think to understood so far is that Google Maps for example is ...
4
votes
1answer
96 views

Creating shapefiles using textfiles in QGIS

I have a shapefile in QGIS which has polygons in it . There are several other attributes for each feature . I want to add another attribute to each feature . The value for this attribute is available ...
0
votes
2answers
61 views

Layered world map

First off I just want to say that I am NOT sure if this is the correct place to ask this question; So if it is not, please direct me to the correct exchange. So for the question: I am looking for a ...
0
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0answers
46 views

Aggregate/merge data upon insert into PostGIS (via gdal)

I am working on a project where I take a large raster file (1.5GB+), put it through a number of image-processing operations, and finally convert it to vector data. Being that the raster is large, I am ...
3
votes
1answer
123 views

Shifting an entire .las file in Z?

I have a set of .las tiles. I needed to edit one of the tiles in Trimble's Inpho DTMaster to remove some noise. The coordinates are correct in the program, showing a my desired elevation. On export, ...
4
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1answer
1k views

Sketch event in Openlayers 3 drawing interaction

For drawing Polygon in OpenLayers 2 we could use as follow: function drawEnd(){ ... } function putPoint(){ ... } function sketchModified(){ ... } function cancel(){ ... } var ...