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

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3
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1answer
144 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 ...
1
vote
2answers
39 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 ...
1
vote
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
votes
0answers
69 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
votes
0answers
91 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 ...
1
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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....
1
vote
1answer
58 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 ...
0
votes
0answers
29 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
votes
0answers
40 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 ...
0
votes
0answers
63 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( ...
0
votes
0answers
37 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
votes
2answers
119 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 ...
1
vote
0answers
83 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 ...
1
vote
0answers
33 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
votes
1answer
122 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
votes
2answers
146 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....
1
vote
1answer
80 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
votes
1answer
73 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: ...
1
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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 ...
1
vote
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?...
1
vote
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
votes
1answer
112 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
votes
0answers
39 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
vote
2answers
255 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
vote
0answers
54 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
votes
0answers
70 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 ...
1
vote
2answers
30 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
votes
2answers
127 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
votes
1answer
317 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
182 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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0answers
61 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
vote
2answers
163 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
vote
1answer
195 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
votes
1answer
98 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
22 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....
1
vote
0answers
96 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
votes
1answer
91 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 ...
0
votes
0answers
30 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
vote
1answer
66 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
vote
1answer
138 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 ...
1
vote
0answers
59 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 ...
2
votes
2answers
109 views

Splitting vector file by date (year) but column containing dates 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 layers....
0
votes
1answer
38 views

Polygon to multiline object in ArcMap?

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 ...
0
votes
0answers
17 views

Arrangement of vectors and matrix in text file?

My ASCII file has a vector of latitudes, and the indices of those latitude values tie latitude values to the data sharing the same index. That is, if given: latitude[x=0,1,2,3] = 10, 20, 30, 40 ...
1
vote
1answer
95 views

Viewshed plugin in QGIS doesnt work

I loaded DEM and Point data and as a result i just got black raster (still black after calculation). If I click intervisibility I cant see it like if line data is not there. I tried changing meters, ...
4
votes
1answer
67 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
votes
1answer
411 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
vote
1answer
40 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?
2
votes
3answers
99 views

Extracting a small subset of an .sdc file

There are some line features in the form of an .sdc file. I do not need all the data in the file, just a very small subset of it. I understand that .sdc files are highly compressed, and my file is ...
1
vote
1answer
253 views

Vector layer visibility using min/maxResolution is not working in Openlayers 2

I am using OpenLayers 2 and Geoserver. I have a few WFS layers and an OpenStreetMap as a Baselayer. I want to change the vector layers' visibility at certain zoom levels, by using min/maxScale or min/...