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

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48 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. ...
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2answers
257 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 ...
3
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2answers
152 views

Add rectangle polygon

I have a polygon shapefile layer. I want to add a rectangle polygon (just like in Arcmap), and another one using the previous polygon edge. I need it to be accurate, my hands do not meet this ...
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0answers
47 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 ...
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1answer
188 views

How to project vector data in QGIS 2.2?

I'm running QGIS 2.2 on Ubuntu 14.04. Trying to project data gives me a hard time right now. The last time I did that was in 2.0 and I basically changed the projection by saving the data as a new ...
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1answer
151 views

Produce line from components, length and angle

I have a CSV file, or point data file which includes information about line vectors which I have previously calculated. This file is outlined as such: x, y, dx, dy, length, angle(east_from_north) ...
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0answers
76 views

Method for identifying upstream segments

I need to add to the attribute table of a stream network layer a column that can identify all upstream segments that contribute to the segment (for each segment). My best idea at the moment is to ...
3
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2answers
255 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!
2
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1answer
61 views

unable to draw polygon without attribute window popping up?

I'm fairly new to QGIS and an trying to draw a polygon via "Adding Feature". When I make the first left click to start, the attribute window pops up instead of letting me continue on with additional ...
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0answers
419 views

How to automatically vectorize data from WMS?

I am facing a problem, when I have a historic map in WMS layer and I need to get buildings from this map (approx. 2000) to vector layer fo further analysis. Is there any workflow how to ...
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2answers
561 views

Openlayers: Get Start and End Points of Line Vector Features

I'm trying hard to get start and end of lines from a vector. The line vector is loaded from a kml-file. For now, I tried to iterate over features in the vector and grab the start point and put it in a ...
2
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2answers
194 views

Converted GPX file has null values in open attributes

I'm an absolute newbie but I think I'm doing this right. I've got a bunch of .fit files from my garmin. I can use GPSBabel to manually convert these to GPX XML and the map looks fine after the ...
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1answer
192 views

Get lat/lon points from image pixels

I need to build an application with the following requirement: shows a map .png picture to user. then, users select several points around the map (I can get the x/y pixels from each point) based on ...
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1answer
520 views

How to indicate flow of a watershed feature?

While tracing and digitizing rivers, streams, rivulets, etc., is it possible to indicate the direction/flow in the shapefile on QGIS? I'd like to avoid using map labels. Ideally, when done tracing, I ...
2
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0answers
162 views

Is there a decent algorithm in QGIS Process Modeller to create a grid?

I am using Process Modeller to automate merging several vector layers and then creating a grid to cover the extent of the merged layer. There are functions which already exist which are not listed in ...
0
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1answer
151 views

get and change style property openlayers

i need to change the property of some style after its created, and i need to change it with knowing only the string of the property name. i am getting string like "fillColor" and value like "blue", ...
1
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1answer
132 views

QGIS: Line to polygon conversion

Currently we are working in a geological project..in which all the Contacts, Linear & some other geological features have to be captured. The thing is most of the features have to be Captured as ...
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1answer
121 views

QGIS batch affine transformations

I have multiple polygon and line shapefiles on which I would like to apply a translation so I was wondering if it is possible to batch process them (maybe with graphic modeler ?) or do I have to ...
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1answer
136 views

How to Warp vector file based on control points in ArcMap?

I have a very comprehensive polyline file that, when compared with imagery, is obviously offset by a few hundred meters, but the offset varies from one area to another. It would be easy for me to ...
0
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1answer
60 views

Producing gradients between shapefiles and using original boundarys as isoclines (lines)

to produce a bathmertical map of a river bed I draw shapefiles showing the different depths based on satellite images taken during different tidal levels (deepest, 2nd deepest, 3rd deepest, shore ...
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2answers
62 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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1answer
74 views

Select all features close to clicked

I have an openlayers map with more then 20000 features not in wms, only in vector layer. I have a control to select features, but sometimes it's really hard to select, specially the lines, and also ...
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2answers
54 views

Adding time stamps to animation slides with OSS tools

I would like to create an animation with time lapse values printed on the PNG file. For this purpose I have created in QGIS a vector layer that stores timestamp and temperature value pairs for various ...
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0answers
51 views

How to raster vector- and shape-files correctly

does anybody know how to convert vector- and shape-files correctly? Doesn't work with tab Raster/convert/vector to shape files. The output always contains strange input-data (wrong and strange ...
4
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0answers
32 views

Projecting polygon when calculating its area? [duplicate]

I have a broad range of polygons (in vector format and in SpatialPolygonsDataFrame class), some going east-west, others going south-north, while even others span polar regions or very large ranges as ...
3
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1answer
208 views

Looking for Android, offline, mobile app for field campaign?

In the frame of an international project in agriculture monitoring, I have to propose a mobile app that will be used as a reference for field working. The minimum requirements of such an application ...
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1answer
68 views

why can't i export geometry data from a shapefile?

I saved the layer using "vector save as" box but even when adding GEOMETRY=AS_XY in the layer box, the csv only showed the id and no gemetry data.
2
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1answer
303 views

Why do layers appear in the wrong order in QGIS 2.2?

I have a problem with in which order my vector and raster layers appear in QGIS. I have raster that I want to be the background of my other layers (vector). I place the vector layers on top in the ...
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2answers
297 views

Techniques for Filtering the Attribute Table in QGIS's Print Composer

For the legend of a trail map I'm working on I'd like to show the trails and their lengths. I have this data in the table. The problem is that not all of the features (lines) have a name or length. ...
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2answers
47 views

Creating Many Uneven Buffers

Qgis 2.2, Windows 7 I am looking to create buffers around city lights (the raster). Currently, I have simple polygon buffers around the point layer (oecdminusa), but this is not accurately capturing ...
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0answers
71 views

Calculating Percent Overlap Between Distribution Maps

Hello there, I am currently trying to calculate the percent overlap (basically the total amount of overlap where these two species come into contact) between Lithobates catesbeiana (first image) ...
4
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1answer
503 views

How to add tree height values to raster / vector data?

I am new to working with raster data and I am trying to teach myself a few things. I have what I think is a simple problem but I can't seem to figure this one out after a few hours of searching Arc ...
0
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1answer
25 views

vector file is used by two mapsets at a time in grass gis

i want to study about vector processing.if a vector file is used by two mapsets at a time, which one will be saved first and why.if a team want to work on the same set of shape files, what is the ...
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0answers
305 views

Editing QGIS point layer: retrieve attributes of intersecting line layer

I'm creating a custom editing form using QGIS 2.0 and would like to modify the mouse event when creating a point. I've gotten a start by reading this thread: How to programatically check for a mouse ...
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0answers
82 views

how to easily serve vector layer with extra attributes for openlayers

On a website I'd like to show an openstreetmap with buildings colored by a certain feature (tag). So far I was able to extract the buildings for a bounding box, save them as an osm file and load it ...
5
votes
1answer
257 views

Generating a vector contour map of fictional terrain

Originally I had asked this on the Graphics Design SE but after some realization of the question I was asking, it's probably better to ask it here. I'm making a fantasy world map in illustrator that ...
1
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2answers
461 views

CartoDB map in openlayers

Is there a way that i can upload my CartoDB map in Openlayers as a WMS layer or Vector layer. Here is the my CartoDB map link. http://cdb.io/1nxdrpf
1
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2answers
88 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 ...
0
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0answers
99 views

Turn vector layer in raster layer based on cost

Hy, I am trying to rasterize some vector layers into raster layers and I know this is possible with QGIS by using the rasterize function in the raster menu but I don't know how to do the following ...
1
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2answers
212 views

QGIS 2.0 Automatic generation of a vector layer out of a point layer

I am an environmental engineer and the aim of my QGIS 2.0 project is to visualize the results of a sewage water system inspection. In a first step I included the hoppers from a csv file and added a ...
2
votes
1answer
980 views

Using Affine Transformation to expand polygons in QGIS

I have a shape file, and I'd like to grow each feature by 13.7% or 14%. The program crashes every-time I try to use affine transformation. Any recommendations? I don't have a license for ARCgis. ...
1
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1answer
98 views

QGIS combine Vectorlayer and Rasterlayer to one shapefile

I have to create some Thematic Maps, especially Choropleth Maps on Matlab. Therefore i've found a shapefile which I can use, but need to draw some lines there. I've imported my shapefile as a Vector ...
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0answers
119 views

How to achieve labeling in openlayers as Google did?

I am tried to find a solution for my question. Please look the images below. Google Google are awesome!!.. They are doing fantastic technique in labeling part. Please look the marked labels, the ...
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3answers
165 views

Invalid geometry message when using Difference tool

I am using the Vector \ Geoprocessing \ Difference tool to get the resulting area when taking a) current ground disturbance away from b) historic total ground disturbance to give c) what has been ...
1
vote
1answer
256 views

How to automatically transform between base layer and vector layer in OpenLayers

I have a simple example on http://jsfiddle.net/29bsw/ I have a map with an OSM layer as base layer and an additional vector layer. The projection of the map is defined as EPSG:900913 and the ...
0
votes
1answer
211 views

Geomedia WebMap WFS to vector marker layer in Openlayers

Looking for minimal example/advice on getting a WFS service to show up as a vector layer with markers/icons in Openlayers map. I have created the WFS service in Geomedia WebMap 6.01.11.19 and the ...
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0answers
78 views

Is there any GRASS command to measure the distance between a point in rastermap and another in vector map?

I have a question about WinGRASS 6.4.3. Is there any GRASS script command to measure the distance between a point in rastermap and another in vector map? I have a raster map and a vector map. Raster ...
3
votes
1answer
225 views

Where to get the modern Constellations as a vector File?

Does anyone know where I can get a vector version (shapefile/TAB) of the modern star constellations for the entire sky? Wikipedia has a SVG - ...
0
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0answers
27 views

Show the paths but not roadsides and driveways in the line layer

I want to display paths in the woods but the paths are all in One (line) layer that contains all roadsides, pavements, drivvays, but also paths, tractor road and other relevant roads in, and up to the ...
0
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1answer
73 views

How can I add vector tiles to my tileserver?

I created my own tileserver under ubuntu 12.04 as described here: http://switch2osm.org/serving-tiles/building-a-tile-server-from-packages/ now I want to serve the tiles as vectors, I found this: ...