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

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1answer
87 views

Raster and vector layer in the same CRS don't match

While adding multiple raster and vector layers (and setting them all in CRS WGS84) in QGIS 2.2, they don't seem to overlap. Interestingly enough, only raster files overlap between each other, the same ...
2
votes
4answers
93 views

How to set a minimum point snap distance?

There are two points: A and B. I need to snap any points within a 65 m search radius (blue buffer) of point A. However, the snap distance of B needs to be exactly 5m apart from A (i.e. located ...
6
votes
3answers
5k views

Finding nearest raster cell value based on vector point?

I have two layers in ArcGIS: One is a vector point and the other is a raster layer. I want to append the value of the raster data grid to the vector point. The problem is the vector point is away from ...
0
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2answers
528 views

Vector Tile Rendering on iOS

I'm developing an iOS app for displaying my own custom map data (on GeoServer). The SDK I'm using to display my map is route-me (Alpstein fork) as the map viewer for now. route-me supports raster ...
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0answers
52 views

Can I create a cross section from points along a line without using a DEM in QGIS?

I have a set of points perpendicular to a river and would like to present a cross section of them. Like a simple graph in Excell for example, with Z as y axis and distance along the line as the x ...
1
vote
1answer
62 views

Calculating percentage of polygons within specific areas using ArcGIS for Desktop? [closed]

I have a parcel layer and I am trying to determine the percentage of each parcel that falls within specific zones. I tried tabular intersect but it just returned an empty output. I'm using ArcGIS ...
0
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1answer
69 views

Difference in vector / raster area measurements

I'm comparing raster and vector distance zones. So I created a line, calculated the Euclidean distance, and reclassified the raster to two zones: from 0-10m and 10-20m. To compare it with vector ...
3
votes
2answers
138 views

Is it possible to add house numbers using the Mapbox Street Vector Tiles source in Tilemill2?

Title says it all. Does anyony know if the house number is included in Mapbox’ vector tiles, and if so how to access it for styling? Thanks for any advice!
3
votes
1answer
67 views

Comparison of vector file formats

Does anyone know of a chart or table that would explain the benefits / shortcomings of the different vector file formats, eg. .shp, .gml, .kml, .gdb. It seems that ESRI shape is still quite prolific, ...
0
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1answer
56 views

How do i rescale feature classes of different scales for intersect analysis?

before I intersect 2 feature classes of different scales (e.g. 1:200,000 soil map and 1:25,000 land use map), should I rescale them like how u would resample raster datasets to the same resolution ...
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0answers
33 views

QGis road graph plugin can't be configured

I am using QGIS 2.2.0 Valimera on a Windows 7 ultimate 64 bit version. I want to calculate the shortest path on a line layer (OSM street layer) with the road graph plugin. The settings option to ...
0
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1answer
39 views

how can we convert vector data to raster data in geotools

In my project iam able to open and save shape file. I want to convert this vector data to image format as a tiffimage plese help me the procedure to do the same.
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0answers
40 views

rasterize table polygon postgis 2.1

I would like to rasterize a postgis 2.1 polygon table, but I don't undersand how to create the SQL function syntax for ST_AsRaster. My vector table has 3 fields: gid, recharge, and geom. The SQL ...
2
votes
1answer
281 views

Possible workflows for shaded relief representation as vector

I am looking for a good workflow on how to represent relief on a map as vector (e.g. for further processing in Adobe Illustrator or Inkscape). My inspiration is the present google maps at zoom level ...
4
votes
1answer
229 views

Loading a multipoint shapefile in R

This issue has only been raised in the community once, two years ago, to the best of my knowledge. I think it's high time to raise the issue again! readOGR, from the rgdal package, cannot handle ...
1
vote
2answers
63 views

Trace vector map from GeoTiff, Garmin

My goal is to create a vector map for my Garmin GPS by tracing over a topo raster. The vector data would be exported in ESRI SHP format and later converted for Garmin. So far, I can load the geo ...
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0answers
57 views

OpenLayers DrawFeature Vector parameters

"Dear all, in my map application I am using a Vector/DrawFeature approach like this: var refresh = new OpenLayers.Strategy.Refresh({force: true, active: true}); var proj = "EPSG:900913"; var ...
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0answers
53 views

gdal read whole geotif band into vector

i have another c++ GDAL question. I try to read alle elevation data out of an GeoTiff file into a c++ vector so that i can get elevation at x,y like this: vector[x][y]. I also like to use this data to ...
1
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1answer
647 views

Drawing pie charts with vectors on OpenLayers?

Is anyone got any examples of drawing pie charts with vectors as markers on OpenLayers ? Cheers,
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0answers
50 views

OpenLayers.Layer.Vector and BBOX

i configured this on my client page var kmlLayer = new OpenLayers.Layer.Vector("KML" ,{ strategies: [new OpenLayers.Strategy.Fixed(), new OpenLayers.Strategy.BBOX()], protocol: new ...
0
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0answers
9 views

dividing a line vector road in QGIS [duplicate]

how do I divide a road, say of 10 km length which I have digitized from Google Earth, into regular intervals of 1 km? The roads are not straight and have been digitized around ponds in human dominated ...
1
vote
1answer
28 views

Load a vector only for a specific zoom

I have a map with 4-5 vectors. At the beginning, the loading of the web application is very very slow, but was fine before I've added a new one vector, which is used only for little zooms. Is it ...
17
votes
4answers
12k views

How do I load OSM vector data in QGIS 2.x?

In QGIS 1.8 I used the openstreetmap plugin to request data from the server, or open a .osm XML file, which produced 3 layers (polygons, polylines and points) in QGIS. This was great (give or take the ...
6
votes
1answer
546 views

Easily calculate “roundness/compactness” of a polygon

I am trying to find ways to quantitatively describe the shapes of various polygons. For my project, these polygons represent lakes, rivers, lagoons, and parks. So they can be almost any shape. One ...
0
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0answers
32 views

The difference when querying raster and vector

Hi everyone I have two queries have the same meaning but different results. Why is there a difference?. Queries are true? query 1: query 2:
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1answer
34 views

How to put marker on vector layer with lat/lon on QGIS [duplicate]

I have a vector layer, and bunch of lat/lon values. I want to put markers on the vector layer for each lat/lon pair. I have never used QGis, would you help with it. thanks.
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0answers
77 views

PyQgis: How can I “append” features to a Vector Layer instead of “stacking” them?

As I read data from a text file and add points to a QgsVectorLayer (as well as related attributes), each new record gets 'stacked' on top of the previous one in the Attribute Table (and within the ...
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0answers
16 views

Is it possible to add XML data as DataStore inside GeoServer?

I have multi-polygon with feature information in xml Some kind like below: <polygon> <color>red</color> <coordinates> 125.94517419942997,37.080000000100085 ...
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votes
3answers
74 views

ArcMap Change Values Greater than Standard Deviation of Mean to Zero

I have a feature class with greater than 1000 features and I would like to change all values greater than 2 Standard Deviations to a Zero. Seems like I could possibly use Field Calculator for ...
0
votes
1answer
38 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 ...
1
vote
1answer
62 views

label vector line with multiple attributes in QGIS

I have a line with two 2 attributes. I would like to display both information along with the line in frequent interval, one info above the line and the other is below the line. I am working in QGIS ...
11
votes
1answer
6k views

Merging adjacent polygons in shapefile that has been split at tile boundaries?

I'm currently using building data from the Ordnance Survey Vectormap District and I've noticed that a lot of building polygons are split in 2 because of the way the OS split up the shapefile. This is ...
0
votes
2answers
365 views

How to Resolve Inconsistent OpenLayers vector position Over Google map [duplicate]

I have an OpenLayers map with a Google base layer and an OpenLayers vector layer on which people can draw their own bounding boxes using the DrawFeature control. I have found that, as you zoom in, ...
1
vote
1answer
452 views

Merge two maps with OR operation in GRASS

I have two vector maps. The two maps cover the same area but are split up into polygons differently (i.e. if you were to imagine one map placed above the other, the lines defining the polygons would ...
-1
votes
2answers
95 views

Counting raster points within boundaries in another layer?

I know this question is similar to some out there, but I have tried all the 'solutions' and none of them are working for me. I am using the latest version of Qgis. I have a raster layer with ...
0
votes
1answer
60 views

Issue clipping vector file with QGIS (geoprocessing tools)

I am trying to clip wind speed data (.shp format) to Canada's provincial boundaries (also .shp format). I am using the clip feature in vector > geoprocessing tools. For some reason the function always ...
3
votes
2answers
326 views

Split Lines at Intersection of Other Lines

I have two line layers (roads and contours in this example) and I would like to split the roads layer every time it crosses/intersects a feature on the contour layer. I can't seem to find a tool that ...
0
votes
1answer
44 views

TileStache can't find spatial ref for vector layer

I have a query based vector layer in my TileStache configuration, and it's hitting this block of code if layer.GetSpatialRef() is None and driver_name != 'SQLite': raise KnownUnknown('Couldn\'t ...
1
vote
1answer
100 views

Iterating over selected features in QGIS Processing

I used to be able to iterate over selected features using the following script in v2.0. import processing features = processing.getfeatures(layer) for feature in features: #Do whatever you need ...
1
vote
2answers
94 views

How to align/georeference distorted vector layers in QGIS?

I've got a shapefile which has been digitized from a strongly distorted historical map, and would like to align it as nicely as possible to another precise shapefile layer. The transformation must ...
0
votes
0answers
34 views

How to set pen width of rivers based on scalerank attribute (QGis 2.2)?

I have a Vectorlayer from NaturalEarth.com with riverdata that includes "scalerank" information. Now I want to display these with different pen width based on their scalerank, like this: scalerank 1 ...
7
votes
1answer
506 views

Why do vectors disappears when zooming in?

I have imported a .gpx file into qgis and separated the track waypoints using Vector > GPS > GPS tools. When viewing at full extent I can see the original track and component waypoints. However when ...
0
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0answers
20 views

Changing tracks to vectors in a grid

This is a version of a question that I posted on the GRASS list, but I didn't get any suggestions there. I would like to overlay a grid (cell size about 500 m x 500m) over an animal track created from ...
1
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0answers
35 views

MapServer: UV_ANGLE not calculated correctly?

I'm following this example given on the MapServer website. But the angle of the raster is incorrect: The data is my grib files is correct, and should not yield these perfect opposite directions. ...
0
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0answers
21 views

Is it possible to sort by Layer Name when adding vector data from file geodatabase in QGIS?

Is it possible to order the data alphabetically when adding data from a file geodatabase in the Select vector layers to add... window in QGIS? It is ordered by the Layer ID number, with no way to sort ...
0
votes
2answers
46 views

Rasterization in different bands

I have a set of vector based shape files, representing different types of ground coverage in a city (for ex: roads, buildings, open field,...). For the algorithm that I want to run on it, I need just ...
0
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0answers
16 views

Mapserver dynamically line

I'm a beginner for GIS especially for Web GIS that's implementation to mapsever. I created a project that I've uploaded at dedyfuadi.web.id . For the map features, I made by QGIS 2.0 and for ...
4
votes
1answer
452 views

How to export 2D vector graphic from ArcScene to Illustrator?

I need to know how to export 2d vector graphic from ArcScene so I can edit it with Adobe Illustrator. I've tried changing the options when I export 2D scene as AI file or PDF file, but they always ...
0
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0answers
39 views

Assign a particular projection for un-projected raster/vector files in a folder/sub-folders

We are having 1000's of raster images/vector (shp,tab,dxf) files in a folder/sub folders. Is it possible to check the projection of those and if it is an un-projected one? WGS 1984 has to be ...
0
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0answers
32 views

Finding normal vector to DEM

I have a DEM grid (Surfer, or whatever format) and an x,y position on that grid. I also have a series of depths from the surface. I need to calculate, for each depth, the x,y,z of the projected ...