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

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112 views

OpenLayers Strategies

Can we use the strategies OpenLayers.Strategy.Fixed and OpenLayers.Strategy.BBOX simulataneously on same vector layer?
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1answer
445 views

Running Maperitive on a Mac

Really basic question, but I need details and help running Maperitive from my mac. I've tried launching it from the terminal and tried running it through WineBottler. If anyone has experience with ...
1
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1answer
147 views

reclassify vector data from multiple source data fields (ArcGIS) (ModelBuilder)

I am using ArcGIS 10.1 and ModelBuilder. I am not familiar with Python. My question is very similar to ReClassify Vector Data Between Values . However that question is about reclassification using ...
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0answers
106 views

Loading Vector Layer PyQGIS Issues

I am trying to follow PYQGIS documentation for loading a shapefile from inside a script. http://www.qgis.org/pyqgis-cookbook/intro.html I was able to set the datasource and run the QgsVectorLayer ...
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61 views

Vector/Raster Intersection - Speedup and replacement for ST_Centroid

I have some raster data which is the altitude above sea level and also some vector data which represents building outlines. What I want to do is grab some buildings outlines and fetch all the raster ...
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0answers
129 views

How to render a transparent raster layer on top of one or more vector layers with PyQgis?

I been trying to render a map with a 3 vector layers and one raster layer. The idea is that the raster layer should be on top of the other 3 vector layers. The problem is that even when I add the ...
2
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2answers
131 views

Convert ASCII Grid Colorized to Raster

I have an ASCII Grid file + .prj file and can visualize this in qGIS. I can colorize it by going to properties and using a Pseudocolor Ramp. However, I want to export this now as a TIFF / Raster. ...
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0answers
93 views

convert vector with multiple attributes to multiple rasters

I have a vector polygon feature with multiple attributes/fields. Ultimately, I want to convert it to a raster 'stack,' whereby each of the attributes/fields will be a different band of the raster ...
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1answer
183 views

Creating an “average” polygon

I found this thread in the old ESRI forums with the same type of problem I am facing today. The solution to the problem is explained in little detail and since I am not an expert, I was wondering if ...
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1answer
51 views

How to edit a table in GRASS?

How do I edit a table in GRASS? When importing a vector into GRASS from QGIS, all the attributes are lost and I need these to continue with my analysis.
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1answer
299 views

OS Vectormap GML files into PostGIS

I am having difficulty in efficiently dealing with OS Vectormap data that comes in GML format. In the past I used the Plugin for QGIS (OS GML Tools) to batch convert folders of compressed GML (.GZ) ...
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1answer
55 views

Area surface doesn't match

I have three municipalities with a total surface of 178 sq km. I want to analyze land cover of those municipalities using both LANDSAT images with a pixel size of 30 x 30 meters and SPOT with a pixel ...
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0answers
41 views

Align OpenLayer raster with OS Mapping Vector

I have an OS Vector map of a town in Ireland. When I load the Google Satellite Raster from the Open Layers plugin, the results are slightly off, by about 2m, probably due to ariel persepective. I'm ...
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1answer
181 views

Add a popup to a Vector LineString in OpenLayers?

Is it possible to add a popup (without a marker icon) to a Vector (LineString)? This is my code, if possible, how to change it to add the popup? I need the popup to display some additional ...
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1answer
91 views

show dwg,as background not as vector

I have some dwg files that i need to show as background on my map, but the DWG is not need to be vector layers, i need only to show them with out the need of using. if i am trying to convert it to ...
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1answer
143 views

Sum of values within a buffer polygon

I need to do the following in QGIS and hope so much anyone could help. I have a vector layer with points. Each point represents a firm with the number of employees in the attribute table. I want to ...
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0answers
59 views

Can I edit WMS layer or KML layer?

I am using Openlayers and until now i have been using OSM as background and i got points from my db (mySQL) and add them to vector layer, then i could modify them and save it back to the server. now i ...
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0answers
47 views

Moving legend items up and down in QGIS

How can I change sort order in layer properties styles tab? The only way I've found is to change their labels and order by it.
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1answer
49 views

Speeding up raster to point set function

I have written the following function that takes a raster (always non-skewed) and returns a set of points. As I'm executing it millions of times in my queries, I'd like for it to be super-optimized ...
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129 views

Issues when importing line shapefiles into NetworkX

Note that although I am using Python Console from within QGIS for this, I don't think it's a QGIS issue. Below is the difference of how NetworkX is dealing with 2 line layers created by the same ...
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2answers
64 views

cutting and extending one polygon layer in function to the other layer boundaries

I'd like a methodology that can edit my vector layer, extending and cutting the features in the polygon layer "cap_agricola" within the boundary layer "sp_edr", I would like to solve this problem in ...
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0answers
159 views

Line segment connectivity analysis in FME

I have a set of line segments, all of them snapped at the endpoints: As seen in the above image, the line segments appear in groups (4 in this example). Question: I would like to determine which ...
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4answers
733 views

How to get vector data from OSM to use in QGIS?

How do I get data from OpenStreetMap which I can then edit in QGIS layer by layer? What is the best OSM output and what / how do I get to a suitable input for QGIS? OR...is there another appraach to ...
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1answer
131 views

How to draw a custom map on top of base layer

I'm looking for the easiest way to draw a custom layer and export it as a tile cache. Basically what I would like to be able to do is load a base layer, and then draw objects and annotations on top ...
3
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1answer
122 views

Creating a radius of influence around points

I have a vector file of points. What I need to do is create a circle with a radius of 12km round each point. Would it be possible to then find out what percentage of my total map is covered with ...
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50 views

GRASS GIS SDTS Manipulation

Preface: I'm a total GIS noob. Flame away. I'm learning GIS in my free-time and with free resources. I realize that is likely going to force me on the learn-fast-or-giveup track, but here it goes... ...
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2answers
281 views

How to delimit hinterland boundaries among multiple city centers?

I need to delimit city boundaries basing on centers'magnitude. CenterA's employment/CenterB's employment = (Distance from centerA to break-point E/Distance from centerB to break-point E)^2. AB=AE+BE. ...
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2answers
119 views

Can Vector grid shape file be clipped with Satellite image in qgis?

I am working in open layers plugin in Qgis . in order to project the satellite image wit respect to vector shape file i am having, Andre Joost suggested me to create a vector grid with crs sysytem of ...
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1answer
389 views

Why does QGIS hang when I try to create a vector grid?

I am working in open layers plugin.i need to project the satellite data with respect to vector data shape file i am having .for that Andre Joost suggested to create vector grid with vector data ...
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1answer
306 views

Selection problem in WMS layer using OpenLayers

I added 4 WMS layers (three polygons and one have point geometry) from GeoServer on my webpage My requirement is: I have to select a single polygon of one wms layer using a mouse click. After the ...
4
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1answer
1k views

Google maps android vector rendering : how do they make it that fast?

Most of the question is in the title. If you are on android (I believe its the same on IOS) and use maps you will notice the quality of the maps app and how the vector maps are drawn in a very fluid ...
4
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2answers
413 views

Vector Mapping for iOS?

Are there any vector map data providers with API's, that i can use to build my app on iOS natively (not on a webview). Specifically im looking for: For a library/framework that uses existing map ...
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100 views

OpenLayers Copy Feature without Geometry Duplication

I am working on an OpenLayers project with considerable amounts of geometry data for linestrings. I would like to create a duplicate of the features within a vector layer, but have this duplicate ...
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152 views

How to Calculate Shortest Path Routes for Multiple Start and End Points?

I'm new to QGIS and was wondering, is there a way to calculate shortest paths along roads for multiple sets of points? So basically what the roadgraph plugin does but for a series of start and end ...
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4answers
2k views

Displaying a KML File on a Vector Layer in OpenLayers

This should be straight-forward, but I am beating my head over it. KML will not display. I have tried from same server and remote server to ensure it is not a cross-domain issue. The KML file loads ...
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0answers
136 views

How to create a line layer which connects a point layer to a line layer?

In the map shown below, I have manually created the dummy lines (in green). Using python, and without using PostGIS or sextante, I would like to automate the creation of these dummy links between a ...
2
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0answers
207 views

OpenLayers Google v3 and other layers drift apart

I'm stuck. My code works with OSM, but I need it to work with Google as well. The problem is simply that Google v3 and my other layers are not playing well together at all. They don't zoom together. ...
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1answer
283 views

How to append a vector layer using Qgis and Python?

I am working on scripting some data processing using Qgis and Python, but I'm running across issues that I need to debug. Since my data is really large, and run-times can be lengthy, I would like to ...
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3answers
308 views

Export Shapefile To KML - Google Maps Layers/Tiles

I need to convert a shapefile (either polygon shp with millions of polygons or polyline shapefile derived from the polygons) into a format to use online in Google Maps. I currently use GDAL codes ...
3
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2answers
125 views

How to create a hectare raster from vector input data in QGIS

I have a vector file containing points with an attributed value (no. of employes at that location). I need to create a hectare raster with the sum of employes for each grid cell. I'm using QGIS and ...
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20 views

Drillhole Plan Trace in Arc [duplicate]

I'm struggling to find the math to do what I want. I want to plot a top down view of a drillhole in ArcMAP 10.0. I have the beginning UTM coordinate and then for every place in the hole that was ...
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2answers
92 views

How to drag a point and then use savestrategy in OpenLayers

Im trying to use the wfs-t in openayers using the savestrategy. I have created a savestrategy and it works when I for example uses the DrawFeature Control to add a point. A new point is added to the ...
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0answers
51 views

How to simplify vector lines into an overlaid grid in QGIS?

I'm a relatively new user with GIS software (primarily QGIS) and I'm sure this is probably quite simple but I've been trying to find an answer for ages! I have transportation network data for an area ...
2
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2answers
85 views

How to overcome the layer limit on OSX?

I am trying to add many layers to a project in QGIS. After adding approximately 80 layers, QGIS returns this error: "not a valid or recognized data source". There is nothing wrong with the shapefiles ...
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vote
2answers
81 views

How to clear attribute columns from a Shapefile?

I want to clear all columns from a SHP. Only need geometry of features. I use QGIS and Sextante with grass and saga. Is there any tool for this job...
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0answers
205 views

How to set point / line / polygon color and transparency with Python?

How can you set the color and transparency of a vector layer feature in QGIS using Python? Seems like a pretty simple and common task but I can't seem to find answered questions or examples. Any ...
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0answers
42 views

Flow direction for line segments

My sanitary sewer data (shapefiles) is being merged with data from another GIS firm for a large project and they are asking me to flip all my line segments because they believe they are backwards but ...
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0answers
91 views

Problem using grid with a vector layer

I need to establish a model of maritime pollution and I try to use the grid option to work on ocean sectors. I tried to use my grid on a vector file, .shp, with points. Each point is a maritime ...
0
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1answer
144 views

Different Styles Within Vector Layer

Is there any way to configure OpenLayers styling method? I have a vector layer and I would like to style the features depending on a value of a flag variables, so I can't use rules. Lets say I have ...
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2answers
216 views

add a vector point on OSM map

I have managed to show Lat and Lon function init() { navigator.geolocation.getCurrentPosition(function(position) { document.getElementById('myloc').innerHTML="Latitude: " + ...