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

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94 views

how to draw coordinates along the lanes using MultiLineString instead of LineString

I trying to draw lines along the path of the lanes on the map using openlayer3 but i am not getting any lines on the lanes there is no error in the developers console as well <!DOCTYPE html> &...
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0answers
33 views

Using arcpy to add several rasters

I need to do some raster/vector processing on some non-overlapping tiles. My python script needs to find the correct tiles and then extract the raster values and count them up. My script needs to be ...
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0answers
26 views

GRASS: strange classification output and reject map from “i.maxlik”

I am trying to perform a supervised classification with "i.maxlik". I have three bands: 1) elevation (a dem); 2) reflectance (derived from Landsat ETM+ band4); 3) cumulative solar radiation (derived ...
2
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1answer
61 views

Error while executing v.rast.stats command in grass plugin in qgis

I have a vector polygon which I imported in grass. I also have a raster from which I have to extract the value. I ran v.rast.stats command in QGIS 2.12. The command was executed with error. The error ...
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1answer
39 views

Intersect elevation interpolated from CAD file in ArcGIS

I have two datasets - contours and vector (water, roads,...) Vector layers were used as breaklines to generate the contours. Then the contours were generalized a bit. For quality check I need to ...
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0answers
32 views

GDAL/OGR in C++: Opening a vector file

So I'm making a vector file this way: OGRSFDriverH hDriver=OGRGetDriverByName("KML"); OGRDataSourceH hDS=NULL; hDS = OGR_Dr_CreateDataSource (hDriver, fname_dst, NULL); //I add layers OGR_DS_Destroy(...
3
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1answer
50 views

Vector differencing fails in QGIS (due to geometric errors)

I was trying to correct the country shapefile of Uzbekistan for Gas flares: Input layer (the UZB_adm1) differenced by this layer. In QGIS the result was that the overlapping regions - where the ...
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1answer
99 views

GDAL/OGR in C++: Merge multiple vector datasets to single [closed]

I need to merge multiple kml files into a single one. I found that I could use "ogr2ogr -append" but I have to do it through c++ and my Google-fu hasn't been successful so far. So, any ideas? Also, ...
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1answer
149 views

How to ‘invert’ or ‘reverse’ a vector cutline when gdalwarp'ing a raster?

I have a raster of North America and I'd like to remove the larger lakes from it, replacing them with the same no-data value as the original raster. So I downloaded Natural Earth's 10 meter lakes ...
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1answer
80 views

Increasing size of buffer based on field in ArcGIS for Desktop?

I am using vector data from a CSV file and ArcGIS. I can use the Geoprocssing tool Buffer just fine, I use these parameters and ArcGIS does produce what I want, however it is way to small (my ...
3
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1answer
166 views

Why can't I clip my Shapefile?

I've tried all of these solutions (How to clip a line layer based on polygons with QGIS?) and still cant clip a shp file. I'm trying to create a coastal shp file for one region (NW France) from a ...
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2answers
40 views

Resetting 'cat' column in GRASS?

I've got a regular polygon file that looks like this: Unfortunately, this file stems from a v.overlay so that the 'cat' values are are a bit messed up. I would like them e.g. to start in the upper ...
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1answer
24 views

Making buffer zone based on size of attribute using ArcGIS for Desktop?

Buffer zone isn't really the correct word, sorry, but I am not sure how to explain it. I want to make a circle around each attribute based of the size of the value, similar to a bubble map. However, ...
2
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0answers
71 views

Regridding vector values

I'm trying to regrid and interpolate vector values from WAM model output. I got WAM model netCDF output in rotated grid, I need to interpolate it to another grid which is some variant of LAEA ...
2
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0answers
93 views

QGIS 2.12 map composer issue with vectors

i am making a map that includes all kinds of vector layers; the map looks perfect in QGIS 2.12 Lyon as well as in map composer. None of the layers have scale-dipendent visibility; i have the following ...
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0answers
33 views

I clip a raster with a vector mask in qgis, the result is correct but its a little bit of, why is this?

On one side the result is "bleeding" over the vector on the other side its more than one raster pixel from the vector on the inside. How to correct this? http://i.imgur.com/d0v6mqt.png http://i....
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1answer
61 views

Can I make a multi layers pdf from a mapnik xml?

I am playing with mapnik and trying to export multiple vector files as one pdf with multiple layers. For the moment, my vectors get merged when rendering. Is there a way to keep each vector in a ...
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31 views

Spatial Join Points Vector with Raster Dataset using Arcmap

I have a points file of taxi drop off locations and a raster file grid. I am trying to get a count of each point on a raster cell. How do I go about doing that? It is like I am doing a spatial ...
2
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0answers
41 views

How can I measure the distance between many polygon features and either another polygon or a line in QGIS?

I often have to manually measure the distance between a single site and other sites around it, but obviously this can get long-winded and I feel like there must be a much more efficient way of doing ...
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0answers
70 views

Openlayers snapping not working

I am using a vector layer on my map that contains lines like this: var map = new OpenLayers.Map({ div: "map", layers: [ new OpenLayers.Layer.WMS( ...
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0answers
38 views

Detecting features intersecting with Profile Line using ArcGIS for Desktop?

I am using ArcGIS' (10.2) 'Intersect Line' > 'Create Profile Graph' functions (3D Analyst Toolbar) to get cross sections of lines from a DEM raster. Does anyone know, if there is a similiar ...
2
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2answers
127 views

Points that get created in the wrong order when using e.g. QChainage?

I have a polyline layer (road) that I want to use to get a point layer with 1 km between the points. I have tried both 'QChainage' and 'Locate points along lines' to do this. They both work, I get ...
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0answers
96 views

Using MySQL vector with QGIS?

I have a problem with mysql vector; when I connect to the MySQL table (containing a geometry column), the attribute table is loaded correctly, the map is centered properly but the geometries are not ...
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0answers
35 views

pgr_nodeNetwork doesn't place new nodes properly

I wanted to use pgr_nodeNetwork tool to split lines where there's no vertex on intersection. The tool doesn't seem to work as expected, though. It doesn't place new nodes right where the two lines ...
2
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1answer
139 views

PostGIS: How to dissolve vector data

I have a few scenarios where I need to dissolve vector data, and I'm wondering how to do this using PostGIS. What would the queries look like to perform these operations? Below I'll describe the ...
2
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2answers
153 views

Leaflet Vector Layers Not Rendering During FlyTo Animation

In version 1.0 of Leaflet, when using the FlyTo function as per this JSFiddle, is it possible to force vectors to render/ draw as the animation is happening? My current issue is when using the marker....
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1answer
81 views

QGIS shapefile to raster

I have a problem converting a shapefile to raster. I created a point-shapefile using a text-table with some xyz-coordinates. Now I want to convert it into a tiff, where all the areas without values (...
2
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1answer
82 views

Styling line layer based on two attributes in QGIS ? (1 discrete and 1 continuous)

I have found a really helpful tutorial to style points based on two attributes. Is it possible to make style lines based on two attributes? I have a shapefile with streets that have two attributes: ...
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0answers
57 views

Data dependent override on colour and linewidth of line pattern fill not working after upgrade to QGIS 2.12

I have recently upgraded to QGIS 2.12 which has resulted in a problem with one of my projects, whereby the data dependent override of the line width and colour of a line pattern fill and SVG marker ...
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0answers
19 views

Accessing feature legend style name using QGIS?

I have a vector layer classified by some combination of field values. I want to add a field for each feature, filled with the legend style name of the element. How can I do this? via Function Editor?...
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0answers
27 views

How does qgis render vector layer on screen ? How can I do the same in a mobile device

Can you please tell me how does qgis software render the vector layers on the screen. I have a geojson file and I need to map its contents on the screen just like qgis does but without using base map ...
2
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1answer
124 views

Combine digital elevation model (DEM) with point layer (QGIS)

I have two layers: The first one is a digital elevation model (DEM) as GeoTiff. The second is a point vector layer (start and end of street segments). What I want to do: Add elevation information ...
2
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0answers
44 views

Create polygon layer from point data with number attribute where polygon encloses n% of point data attribute value in QGIS [closed]

I have two sets of data, one is the CodePoint Open with the location of all of the uk postcodes, the second is from online form data from which I've extracted the postcode and telephone area code, and ...
1
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2answers
322 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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0answers
60 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 ...
2
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0answers
71 views

Error trying to save vectorfile in QGIS 2.10?

I'm trying to save some changes I made in a vector file (polygons) in QGIS 2.10. The file contains properties and I want to merge two of them into one. I toggled and selected the two and then pressed ...
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2answers
32 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
145 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 ...
2
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1answer
380 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 ...
5
votes
1answer
195 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 ...
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0answers
65 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 ...
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2answers
175 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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1answer
217 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
119 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?
2
votes
1answer
23 views

Multi-string data-set without z layer, applying ordinal values as a workaround

I'm new to GIS and have been learning a lot over the last few weeks, however, I've finally come to a point where I could use some help. I'm working with the pdx_streets data-set from http://www....
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0answers
103 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 ...
0
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1answer
98 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 ...
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0answers
32 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 ...
1
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1answer
74 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 ...
1
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1answer
145 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 ...