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

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3answers
152 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 ...
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0answers
12 views

How to equally space points in a line using QGIS? [duplicate]

How do you place points in a straight line the same distance from each other in QGIS? Thanks
1
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0answers
65 views

Calculating vector area in QGIS

I have calculated a viewshed (ZVI) in OpenWind and opened the raster in QGIS I have then converted the raster to a vector When I open the attribute table there are 4682 rows (features) and there is ...
1
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0answers
35 views

Connect two contour line with calculated line lenght

Is it possible to make plugin for qgis like PEGGER for arcview 3.2? Problem is, how to make path over contour lines with a grade in percent Formula is: K= e*100/G*M ; K=10*100/0.08*10000=1.25m K- ...
4
votes
4answers
4k views

Measuring the distance between lines and points in QGIS

Using QGIS - I have a vector of fault lines. I have point data in the form of a csv which I have also loaded into QGIS. I need to know how far each point is from the nearest fault line then enter ...
0
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2answers
43 views

How to read DGN using GDAL in VB.Net?

Reading a DGN file is a big problem for me. I tried more and more but can't find a way to read a dgn(v8) file by VB.Net. After many search, i found out that GDAL can read and write dgn file, but i 'm ...
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2answers
97 views

Merging shapefile layers not working in QGIS?

How do i merge different vector layers in to one shapefile layer In QGIS version 2.6
4
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5answers
3k views

Problems merging DEMs or other raster datasets? Clipping Raster dataset to vector line?

I have two DEMs that I am going create a hillshade from, and ultimately want one hillshade clipped to a county boundary. I am running into a couple problems, though. When I try to merge the two ...
4
votes
1answer
98 views

Is there a way to split polygons by several lines in QGIS?

I have a polygon (.shp) and a line (.shp) layer. I want to split the polygon in several pieces along the lines that overlap the polygon. Afterwards I want to edit each polygon separately (attribute ...
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1answer
3k views

Openlayers get coordinates of a circle vector after draw

I have made a openlayers map. I have made two features on the map. Navigate DRAW POLYGON I have made 40 sides to my polygon which turns out to be a circle. After I have drawn my circle I want to ...
2
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0answers
148 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 ...
1
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0answers
99 views

Render order of vector features in OpenLayers 3

In a web map application I have a vector layer from a GeoJSON source of country borders. The layer loads perfectly and interactions such as ol.interaction.select works fine as well. I want to style ...
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0answers
44 views

How to add vector KML data in an excel table

How do I take a KML (or XML) vector map saved on my desktop showing for example a election ward and then import it into excel as a data input in a field of data. I have information in excel for ...
2
votes
1answer
377 views

pyQgis in stand alone script, vector loading error

I am trying to use the Qgis functions in a stand alone Python script. I m running Mountain Lion OS, 2.7 Python & the Qgis 2.0.1 Dufour. My main problem is that I cannot get started - I cannot ...
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0answers
47 views

Determine lat/lon intersection on earth from point in space along 3d line

I have a known point in space with a lat,lon,alt. It has a camera with a line of sight and a angle of field of view. I can take the central point and calculate each corner vector of the field of view, ...
1
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1answer
74 views

Loading Vector Layer using python console in qgis

I am using qgis2.6 version and new to pyQGIS. I tried to load a vector file using python console in qgis. I don't know where I am wrong. The layer was not loaded and does not show any error too. Help ...
2
votes
1answer
460 views

How to change layer transparency without changing border lines?

I have a raster image of elevations. I have added a vector shapefile that contains local political divisions. I want to keep the elevation colors, but I want to keep the black lines representing the ...
4
votes
1answer
105 views

Comparing floor and roof areas using QGIS?

I am pretty new in this GIS topic and I would really appreciate if someone can help me with this problem. I am doing a research for university that shall show the available roof area for ...
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0answers
60 views

How to determine Affine Transformation Parameters? [duplicate]

I try to use the qgsAffine plugin to do the transformation. But no idea in its usage. Anyone can post an example. Many thanks!! How to find the transformation parameters? I found some posts suggest ...
2
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2answers
219 views

How to reproject this vector layer?

I have a dxf file and use this tool to convert it to shapefile. Then I apply some affine transformations and get a shapefile that does not fit the shapefiles downloaded from osm (EPSG:4326). I know ...
12
votes
3answers
7k views

How to move vectors to specified coordinates in QGIS?

I have a layer of vectors located around, say, (100, 100), and I want to move them to new coordinate like (1000, 1000). How should I do it? Preferably using QGIS.
10
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7answers
7k views

How to georeference a vector layer with control points?

I have a non-georeferenced vector layer that I need to be georeferenced. With raster layers the task is easy and straightforward, but I have no idea what should I do with my vector layer. I have a few ...
5
votes
2answers
806 views

QGIS affine - form of equation

I am at the mercy of a govt authority who have provided utility information in a cad format with a 0,0 origin and a nonsense grid. About a dozen files, the grid and origin are entirely arbitrary. To ...
2
votes
1answer
76 views

calibrating vector line in qgis

I have loaded GPS points into a QGIS vector layer. I also imported a vector line from a dxf file which doesn't have georeferencing. I would like to fit in line geometry between the GPS points - how ...
3
votes
2answers
307 views

Is there a vector affine transformation tool in QGIS2?

In QGIS 1.8, I can transform my point layer with the plugin "Affine transformation". So, this plugin don't exist in QGIS 2.0. Do you know a method to simply translate (i.e : X -> X+30000) in QGIS 2 ? ...
7
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2answers
6k views

Rotating a vector layer in QGIS with qgsAffine (or other method)?

I would like to rotate a set of vector points in QGIS an arbitrary number of degrees around a central point (or arbitrary point). This is similar to a recent question about creating a regular grid; ...
2
votes
1answer
852 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
116 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 ...
2
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0answers
23 views

Help getting a Mathematical Representation within a Layer's Attribute Table

I'v been playing around with Vector Coding and was wondering if there was any Plugins out there that might let me represent Vectors within a layer as it's Mathematic attributes in the Layer's ...
1
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1answer
89 views

What is a memory vector layer in QGIS?

What is a memory vector layer and how does it relate to the vector layer? Background info: I have a volunteer working with my organization, because of financial reasons we have him using QGIS. He ...
1
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2answers
151 views

Where to find the “contours from points” model in QGIS 2.6?

I can't find the example model "contours from points" in QGIS 2.6. Is there another tool for creating contours from points, besides the QGIS Contour plugin?
3
votes
3answers
130 views

Plotting Geo Points with “by arc centered at” Instructions

A recent Supreme Court decision redefined the legal boundaries of California along the Pacific Ocean: http://www.theverge.com/tldr/2014/12/15/7397085/supreme-court-california-boundaries-map I am ...
2
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0answers
22 views

Aggregate nearby points to develop equally sized regions in QGIS

I have a list of 4,500 points (lat, long, unique id, attribute). I also have a service territory which all of the points fall into. I would like to break the service territory (polygon) into 6 ...
2
votes
1answer
43 views

Appending map to another map using GRASS?

I'm trying to simply append a map to other map, without any sort of geometric operations as merge or intersects, just the original geometries with theirs attributes. This is what I already tried: # ...
2
votes
2answers
190 views

Is there anywhere that I can obtain global UV data in either raster or vector format?

I'm looking for some UV data (currently with no spatial or temporal resolutions in mind, but ideally split into UV-A and UV-B) for the whole earth. Can anyone recommend a source for data like this or ...
1
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0answers
23 views

When trying to save a vector in QGIS a blank dropdown window appears

I am learning and using QGIS Brighton and have hit a obstacle. Everything has been going fine until I started using the experimental generalizer to smooth the contours that I had extracted from some ...
1
vote
1answer
85 views

Raster map & vector boundaryline data for Istanbul, Turkey

I'm looking where I can download background raster map for Istanbul (street map?), and then a boundary line file of the the 39 Districts in Istanbul. Does anyone have any recommendations?
1
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0answers
15 views

QGIS rasterize a styled layer

I disabled information from a vector layer with a styledefinition. Is it possible to rasterize only the styled information in QGIS?
2
votes
1answer
185 views

Convert JPG image to RGB Raster to Vector Data

I am completing an analysis project for my ArcGIS class. I am analyzing the correlation between indigenous populations and food security in Guatemala. Since there is not a lot of information out ...
2
votes
3answers
210 views

Generating a polygon tile index from multiple vector datasets

OK. well this is silly, in that there is no way it should be as difficult as it has been for me to find information regarding how to generate a polygon tile index from multiple vector (contour) tiles. ...
2
votes
1answer
76 views

Problem or ERROR in converting from raster to vector!

I wonder if anyone could help me out, i am kind of a beginner at QGIS. I´ve built a DEM for a project that i am developing than i´ve made the slope raster with the terrain analysis,it seemed that ...
1
vote
1answer
88 views

PyQGIS export to JSON: writeAsVectorFormat and precision

In my QGIS plugin qgis2leaf I am exporting all layers as JSON into a JSON directory. Therefore I would like to enable the user to define the precision in the GUI. The normal "save as" dialogue in QGIS ...
2
votes
1answer
69 views

OpenLayers Only draw features in a vector layer within view

I am dealing with a kml that I am importing into openlayers as a vector layer. This kml has many features so it dramatically slows down the web app. I would like to make it so only the features within ...
1
vote
1answer
36 views

QGIS vector line layer doesnt accept cyrillic letters

In QGIS 2.6 vector line layer doesnt accept cyrillic letters, how can i fix this? For polygon it it works fine but for line and point it only gives me set of question marks - ?????
3
votes
1answer
198 views

Memory Vector Layer Corrupted?

I was working with a large data set that had data for roads, rivers, railways, etc. all together so I decided to break the different data out so I could label it differently on the map and check each ...
3
votes
1answer
163 views

Save map in raster format from QGIS using compression

Is there a method to save a map in raster format from QGIS using compression? For exemple from "Export map" in ArcGIS there are many options to compress the images depending on the file type (tiff, ...
0
votes
2answers
127 views

Using raster to clip vector data

I have high res raster data covering 2million km sq, with a field where each cell has a value from 0 to 100. I need to create a "mask" using the cells with a value over 12 in that field. I then need ...
11
votes
1answer
511 views

SEXTANTE toolbox - GRASS error

I am trying to use the SEXTANTE module GRASS (and SAGA) for vector analysis but whatever function I use I always get the same error:"Could not load layer: G:/closest.shp Check the SEXTANTE log to look ...
1
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0answers
46 views

raster and vector misalignment

my vector and raster datasets align perfectly fine in Arcmap but not in QGIS, any suggestion on solving this dilemma is very much appreciated.
2
votes
1answer
150 views

From CSV file (latitude and longitude fields) to point .shp

How i create a new point shapefile from CSV table? If i have a CSV file with a latitude and longitude fields, is there a method for to have in output a puntal shapefile?