QGIS is a user-friendly, cross-platform GIS application licensed under the GNU General Public License.

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0
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1answer
66 views

check if the district belongs to the province

I'm building map viewer using d3js and data from WFS service. In Poland we have 3 levels of administrative divisions: province district community Using WFS service I can get exact boundaries of ...
2
votes
2answers
366 views

How do I create a polygon layer from multiple touching line segments in QGIS?

I'm trying to create a base map for a Maine Coastal area, and wanted to create a polygon layer of the land cover from the coastline in QGIS. Whether I created the coastline vector layer from the USGS ...
3
votes
1answer
87 views

What is QGIS equivalent of ArcGIS GetCount for use in Python script?

I have a number of layers in QGIS that I would like to select attributes on, and get the feature count for, within a Python script. In ArcGIS for Desktop I have been using SelectLayerByAttribute ...
2
votes
1answer
169 views

Why does writing large shapefiles crash QGIS?

I'm trying to write large shapefiles with QGIS 2.0 API, using Python, which crashes QGIS. The data is composed of simple two point lines and a data table of five columns. A thousand features or so ...
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0answers
35 views

Reducing field length [duplicate]

I have very limited experience with Qgis, and only a very modest amount of basic experience with Arcview and Arcmap so be gentle. I have a shapefile with a text field that has 8 characters in it. I ...
3
votes
1answer
95 views

Is it possible to split a polygon inside another one in QGIS simply?

I can split polygon if I put the points of start and end outside the boundaries. How can I do the same if I have a part that I want to split completely inside a polygon. In Arcgis I can do it if the ...
1
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0answers
219 views

Drawing a road network: offsetting overlapping lines (directed graph)

Say I have a road network defined by a table, indicating, for each arc, its ID, and its head and tail node. In other words, my network is defined as a directed graph. For example, we have two points, ...
3
votes
1answer
114 views

Field calculator uses wrong fields when working with joined data

I am having an issue in qgis table joins. i have a joined a csv file to a sqlite database and common id is used for join. the join is displays correctly in attribute table. the attributes in sqlite ...
4
votes
1answer
199 views

How to horizontally align irregularly shaped point symbol to vector layer in QGIS?

Fairly new to QGIS and searching a method to graphically align my point symbols in the direction of the vector. The symbol represents a water valve in an irregular shape in close proximity to a vector ...
4
votes
2answers
280 views

How can I find the difference between two times (hh:mm) in QGIS?

I have a shapefile of crime reports that includes the time a call was received and the time officers arrived on scene. I want to create response times from the difference in these two values. I know ...
0
votes
1answer
169 views

Why are these WMS/WFS layers not appearing in QGIS?

WFS and WMS layers are not appearing when connecting to servers. I am using QGIS 2.0 and am attempting to connect to: http://www.arcgis.com/home/item.html?id=a0ae91856e3c450996d42d53474a1cad The ...
0
votes
1answer
52 views

Access atributte processing algorithm

I have a doubt. In my plugin I use algorithms from processing sextante. For example: Processing.runAlgorithm("grass:v.to.rast.attribute", None, inputLayer, 0, Indexes, extent, cellSize, -1.0, 0.0001, ...
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2answers
52 views

Which value should I assign my digitalized features?

I have a scanned an old document that contains geochemical interpolated values (no way to work with the digital file). This is the original image: And this is the digitalization I made from it: ...
2
votes
1answer
204 views

Installing QGIS 2.0 with the newest gdal and geos libraries

I want to install QGIS 2.0 on Ubuntu 12.04 LTS. I followed these steps until the final installation command. Before I compiled gdal 1.10, geos 3.4.2 and grass 6.4.3 on my own. In the synaptic ...
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0answers
76 views

export spatial information from table that is joined to a shapefile in QGIS 2.0

I have a table with data values per district for different years. The table looks like this: district name / year / value. The same district is thus present in the data multiple times for different ...
0
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2answers
247 views

What kind of QT widget is the QGIS drawing area?

I mean when open QGIS , and add a vector layer or other type of data. The content will show on the "Drawing Area", i want to ask, the drwaing area is some type of widget or just in the QMainWindow? ...
1
vote
1answer
183 views

Delete duplicate spatial point/points in mssql from a perticular location

I am working with a Spatial data which has a street intersection points.... I get the intersection points from spatial query on street/roads datain MMSQL . but in my case some streets/roads are multi ...
4
votes
1answer
253 views

How do I manually classify graduated data in QGIS?

Is there any way to manually classify Graduated Data in Qgis. In ArcGIS I always used to apply first the natural breaks method to find adequate group sizes for good visual interpretation. Afterwards I ...
1
vote
1answer
435 views

How to remove all selection from all registered layers using QGIS plugin?

I want to remove all selection from registered layer in QGIS using Python. I tried to clear the map canvas using: self.iface.mapCanvas().clear() self.iface.mapCanvas().refresh() but the ...
1
vote
1answer
220 views

How to cut multiple neighboring raster images

I'm looking for a way to cut a larger number of neighboring aerial raster images (each sized 1x1 km, resolution 10 cm per pxel) into four smaller raster images (size 500 x 500 m). I haven't done this ...
2
votes
1answer
284 views

How can I delete a shapefile using OGR?

In my QGIS Python plugin, I use shapefile layers and I am having a problem rewriting existing shapefiles. Is it possible to delete a shapefile from disk using OGR?
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vote
0answers
88 views

Qgis raster interpolation shift

Using Qgis 2.0.1, I'm attempting to interpolate a large point dataset (n > 400K) to a raster surface. I'm using the IDW option in Raster>> Interpolation>> Interpolation, and the resulting ...
1
vote
1answer
386 views

get data from WFS and present in using d3js - correct projection

I'm trying to get data for map of Poland. I found WFS service that provides GML files. It is located under: http://sdi.geoportal.gov.pl/wfs_prg/wfservice.aspx?request=getCapabilities&service=wfs ...
0
votes
1answer
44 views

Some gridlines missing in QGIS Print Composer

I'm very new to this so please excuse my ignorance. I've been working with OS data and my own shape files and had no problem with print composer. Suddenly my OS gridlines are not appearing ...
1
vote
1answer
315 views

How to get additional subbasin areas designated by points in the river network?

Update 14/1/9:I follow this post:Watershed and Stream Network Delineation, and here's my workflow: use Batch Point Generation to create batch points related to designated points(green dots) Batch ...
2
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0answers
47 views

how to assign unique attribute value per neighborhood? [duplicate]

I have a feature class of adjacent polygons and I want to assign an integer attribute value to my polygons based on the following rules : a polygon must not have the same attribute value than any of ...
2
votes
2answers
1k views

Table join with .csv file results in null fields after join

Similar to questions already asked about .dbf files, I'm attempting to join .csv files to a .gdb or shapefile coverage in QGIS. The tables as added to QGIS prior to the join look fine, but after the ...
0
votes
1answer
969 views

How do I solve this dependency error in openSUSE 13.1 when installing QGIS (master)?

I am running OpenSUSE 13.1 and downloading via Yast I get the following error: nothing provides libpq.so.5()(64bit) needed by qgis-master140102-1.2.x86_64 I get three of these errors, for each of the ...
1
vote
3answers
1k views

How to install Fiona to read Shapefile attributes with OSGeo4W?

I´m developing a plugin in Python and I need to read the shapefile attributes, so I found the Fiona API and dbfpy also but I don't understand how to install these packages because I install the QGIS ...
0
votes
1answer
343 views

error of data conversion value getting while importing shapefile in shp2pgsql-gui on ubuntu

Connecting: host=localhost port=5432 user=postgres dbname=tremblement_de_terre Connection succeeded. Connecting: host=localhost port=5432 user=postgres dbname=tremblement_de_terre ...
1
vote
1answer
401 views

When will QGIS use the WMS supplied legend images ? is there a workaround?

I use a lot of wms services with complicated maps : a legend is essential. Qgis displays none of those legends. The URL is quoted in the metadata. example WMS ...
3
votes
2answers
1k views

how to use rectangles ovals digitizing in qgis

i added the new vector layer in QGIS and I want to draw a cicle of 500M or 1000M from center. I also added the pluginn Rectangles ovals digitizing in QGIS. But the options of this pluginn is not ...
0
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0answers
399 views

New values created with QGIS field calculator become null upon saving

I'm having a problem with QGIS. I'm trying to create a new column in the attribute table for a shapefile. The numbers in the fourth column (see screenshots) are currently strings, so I want to convert ...
0
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0answers
205 views

How to add and join Geodatabase Table to Feature Class in QGIS?

After finally figuring out how to open .gdb files from Arc 10 in QGIS, I need to join some tables to the spatial gdb coverages I've opened in QGIS. According to the colleague who converted the .gdb ...
0
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2answers
335 views

Road Graph Export Empty QGIS

Exporting the results of a shortest path analysis through the Road Graph plugin in QGIS 2.0.1 results in an "empty" layer. After running teh shortest path calculator, I selected export --> new ...
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0answers
342 views

Distorted Google Maps layer in pdf export from QGIS 2.0.1

Export of a map from QGIS 2.0.1 Composer to pdf results in distortion (changed scale) of Google map layer. Why?
4
votes
1answer
2k views

How do I install and run SEXTANTE for QGIS 2.0?

I just upgraded to QGIS 2.0, and I have been unable to locate/use SEXTANTE tools. A search with the plugin installer does not turn up anything for "sextante." Any idea what is going on?
0
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0answers
344 views

SAGA/GDAL fails to open grid in QGIS 2.0.1 on OSX 10.6.8

I want to try different grid/raster spline interpolation methods using SAGA in QGIS. I'm using the kyngchaos build 2.0.1-7 for Snow Leopard. Every SAGA algorithm I try gives the following in a popup: ...
0
votes
1answer
155 views

How do I use gdal_proximity.py from the QGIS python console?

How do I run gdal_proximity.py from the QGIS python console?
0
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0answers
71 views

Is there a limitation in quantity of joined tables using spatialite views?

I've one point layer in qgis and several non spatial tables in a spatialite database. Now I want to create a view as you can see in the following: CREATE VIEW testansicht10 AS SELECT ...
4
votes
2answers
2k views

How to add a custom map tile layer?

I am trying to display the following background map in QGIS 2.0: http://server.arcgisonline.com/ArcGIS/rest/services/World_Topo_Map/MapServer/tile/${z}/${y}/${x}. In a custom web map client, this is ...
2
votes
2answers
105 views

How would you illustrate this in a report to a client?

The objectives are simple: They're adding a train station and the goal is to display how far you could get within 30 minutes before and after the new station is built. In this map that I'm working on ...
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vote
0answers
121 views

Whats the status for OSM in print composer QGIS 2.0?

I have a Stamen Toner OSM background on a report am doing. It seems impossible to use "Print" or "Save as image" functions since the OSM is being projected wrong with 10 km or so.. Right now I'm ...
0
votes
1answer
52 views

How to make pen style show up correct in QGIS map composer legend?

As far as I can tell, yes I've updated the legend. See new screenshot. It's like the field width is cutting them, they all begin with one long and then one short line.. I have a several different ...
6
votes
1answer
284 views

How do I change an existing srs in QGis?

I am showing postgis data with srid 28992 (Amersfoort / RD New). But when I plot the geospatial data on a map (with openlayers plugin), the data is shown a hunderd meters off because the datum shift ...
2
votes
3answers
354 views

Shapefile with overlapping polygons: calculate average values

I have a very big polygon shapefile with hundreds of features, often overlapping each other. Each of these features has a value stored in the attribute table. I simply need to calculate the average ...
1
vote
1answer
241 views

How to create labels using 2 columns?

I want to label a layer with 2 columns/attributes. It´s not a problem in Mapinfo, but can it be done in QGIS as well?
0
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2answers
543 views

QGIS 2.0 won't open on OSX Mavericks [duplicate]

I successfully installed QGIS 2.0 on my macbook running OSX Mavericks, but when I attempt to open the program, I get the following message: "QGIS cannot be opened because of a problem. Check with the ...
0
votes
0answers
45 views

Import processing in qgis 2.0 [duplicate]

I know that this question has already asked but no concrete answer has given!! My environment is Ubuntu 12.04 and I'm using eclipse-pydev as IDE. Thanks in advance for helping me.
2
votes
1answer
283 views

Why are xy coordinates displayed in my WGS84 project instead of lat/lon?

I have a project in QGIS comprised of shapefiles and raster maps. The origin CRSs are mostly on ETRS89 / Portugal TM06. I am trying to convert the project to WGS84 to have lat/lon instead of metric ...