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

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HELP with installing QGIS 1.7.3 for a mac

Could someone please help me install QGIS 1.7.3 for a Mac and possibly give step by step instructions? I have already installed QGIS 1.8 for a Mac, however I have heard that the 1.7.3 will run ...
4
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1answer
204 views

QGIS - How to add a geometry to an existing feature that has NULL geometry?

I have a PostGIS table with some polygons having NULL geometry. The rows are correctly displayed in the attribute table in QGIS. As expected, there is no geometry draw in QGIS. My question is how can ...
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1answer
308 views

Mapquest in Qgis, why the blur?

I'm trying to do a simple map in Qgis using mapquest has background. I have read that and followed the scale values but even while using those, I get some bad blur on my map. I can't figure out to do ...
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0answers
286 views

Umlaute not displayed correctly when loading .mdb MS Access into QGIS (1.9.0-Master) with eVis

Good evening, I am loading an .mdb (MS Access 97 or 2003) to QGIS (1.9) via the eVis database conection. Connecting to the mdb, selecting a table and displaying it as a point-layer through the ...
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2answers
168 views

How to translate WIGeoEU projection from ArcGIS to Qgis?

I have a Layer with this projection in ArcGIS: ...
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2answers
615 views

How join attributes for point feature from nearest points in road network

I have two layers: 'linear' - road network and 'point' - points in each linear features intersections. Point layer have in attribute table name for each point features: A,B,C,D,E,F, etc. How add in ...
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1answer
457 views

Create new regions in layer by filling in between polylines on existing layer

I'm not sure if this is possible but would save me hours of work. I have a layer which consists of polylines. Most of those polylines bound areas; houses, roads, etc. Currently I am required to ...
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653 views

Setting up Pyscripter for QGIS dev

I have been trying to set up PyScripter so that I can make use of code completion for QGIS python code. So far, I have been unable to get things to work. PyScripter when set up as per instructions ...
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2answers
4k views

How does manual Label Placement in QGIS 1.9 work?

There are a bunch of questions here related to labeling in QGIS, but it's not clear which version they are referring to, and I know this is something that has changed recently. Hopefully it makes ...
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2answers
2k views

How to display arrows on pipes from upstream to downstream using QGIS?

I am trying to display arrows on pipes of a sewer network so their direction is from upstream to downstream edges of the pipes. I have managed to display those arrows on a polyline layer (which is ...
10
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1answer
591 views

How to automatically populate fields instantly?

I am looking to create an attribute table where the first field is a drop-down menu (I have achieved this by using the 'value map' edit widget), but I'm struggling to find a method for the next part; ...
5
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1answer
196 views

How does QGIS reproject data?

Projection systems are always troubling and I cam across and issue yesterday. I created a buffer and did a select by location using that buffer, however it was producing the wrong results. It would ...
5
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1answer
391 views

Can QGIS access cartodb tables via OGR?

I see that it is possible to access Google Fusion Tables in QGIS using OGRs Virtual Format layer. Shown here and details about the Google Fusion Table driver here. I was wondering whether something ...
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2answers
37 views

Help with 'Invert Overview' QGIS v1.9

I'm using the Atlas functionality in QGIS 1.9 to create a set of maps. So far, so good. But I want to be able to create a smaller map in the margin that acts as a map index. I've seen a blog post by ...
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2answers
741 views

Are there any COGO tools in QGIS 1.9+?

The "Azimuth and Distance" plugin does not appear to be maintained any longer, and has not been transitioned to the new QGIS 2.0 plugin repository. What are the current options for entering COGO in ...
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1answer
662 views

How to get a city road network as line segments?

I want to have road-network information of different cities(New York for example) in the format of line segments(i.e. every road is represented by segment(s)). I want this for experimental purposes in ...
2
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1answer
119 views

How to set default bad layers handler in the python plugin?

I am trying to write a python plugin for QGis. My python plugin will copy a template qgis project into data catalog with ESRI shapefiles. Because data catalogs can vary in its content there will be ...
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2answers
1k views

Manually Adding a Decimal Field to the Attributes Table

I am fairly new to QGIS and search as I might in the manual, training manuals and widely on the net I can't find an in-depth explanation of how to set up a Decimal Number (real) field in my attribute ...
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3answers
1k views

What are QGIS Arcpy Equivalent Functions for Update/Delete Row/Field?

I am trying to reprogram some scripts from arcpy to qgis (1.8 or 2.0) and there are some simple functions that I want to be able to redo but unfortunately documentation in qgis is lacking in certain ...
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0answers
300 views

Qgis libqgispython.so failed to load

I am using Qgis 1.8 and Python (on Ubuntu 12.10) for a couple of month now, but today i got suddenly the error Couldn't load Python support library: Cannot load library /usr/lib/qgispython: ...
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3answers
1k views

Why can't I open postgis layers in QGIS?

I've set up a table in PostGIS using OSM data (converted using osm2pgsql). I know this database is good, because I'm able to import it and work with it in TileMill, but whenever I try to interact with ...
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1answer
316 views

When is Qgis 1.9 being released [closed]

I've been working in the alpha of 1.9 for quite a while (because of doing bug reports) and I like it a lot. It's more than a year since 1.8 was released, so I wonder when 1.9 is expected out.
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124 views

QGIS - How to avoid -2147483648 value from imported CSV?

I am attempting to join a spreadsheet containing all the CIA Factbook Country Comparison Data (many columns) to the existing Natural Earth world countries shapefile. I followd the tutorial here, but ...
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127 views

QGIS layers not adding properly

using QGIS 1.8.0 lisboa on windows 7 pc adding vector layers and they are not adding properly they don't show up in the layers list but they are there when I happen to merge the the layers ...
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1answer
270 views

How to sum the values for bins with the same location?

I have two maps in csv form, each has a latitude, longitude, and value column. Since not all the positions in one map are in another map, is there any way in QGIS to display a new map which only shows ...
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1answer
646 views

Is it possible to override autoincrementing keys when QGIS inserts into SQLite?

I have a table, without any geometry, loaded in QGIS 1.8.0 (from OSGeo4W) via the Add Vector Layer option. The table resides in a SQLite/SpatiaLite database, and has a field named "id" that was ...
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1answer
549 views

How to batch merge rasters using FOSSGIS tools?

I'm working with QGIS 1.8 (gdal 1.9.2) and GRASS 6.4.3...but on Windows 7. I "just" want to merge my raster. I've got a folder with 50 GTiff raster from Lidar data. The aim is to merge raster ...
9
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2answers
728 views

Are there Desktop GIS alternatives to ArcGIS 10.X for topology and vector conflation?

Is there any options other than ArcGIS for Desktop for topological rules and automatic topology integrity enforcing in a Desktop GIS? I am looking for something that will automatically snap features ...
2
votes
1answer
290 views

QGIS custom form: 'dynamic' default value

I am trying to make a custom form in QGIS to smoothen the digitizing process. For this purpose, I put the Edit widget (Layer properties, fields) of one of the fields on 'value map', and I loaded a ...
0
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1answer
121 views

Draw lines for existing list of data

I have a csv file containing information for loads of lines (dates, road names, condition information, etc etc) but which have no geographical information (other than the association of road name) Is ...
4
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2answers
3k views

Setting the extent for a QGIS map using python

I am writing a stand-alone application in Python/QGIS that simply creates maps. I want to load vector/raster layers, set symbology, set extent At the moment, that is all! Currently I am just using ...
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133 views

How to fix ImportErrors when loading Python plugins in QGIS?

I have recently installed QGIS 1.8 in Windows 8. Although QGIS seems to be working fine, I cannot load plugins after their installation. Instead I keep getting this message: Traceback (most recent ...
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275 views

PyQGIS joining a dbf to a shapefile [duplicate]

I am trying to join a shp and dbf file using the PyQGIS API. The code I'll use is below: from PyQt4.QtCore import * vector1 = QgsVectorLayer("path to dbf file", "test1", "ogr") id1 = vector1.id() ...
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2answers
2k views

Merge lines with the same 'name' attribute on QGIS?

I have a shapefile with a few thousand lines, each is a street segment. I'd like to merge all features with the same 'streetName' attribute into a single attribute. I only really care about the name ...
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2answers
676 views

Can I prevent QGIS raster clipper from changing output cell/pixel size?

I have performed a DEM extraction using the clipper tool in QGIS 1.9.0 Master, using a mask layer, the original resolution of the DEM is 20x20 but in the resultant DEM the new resolution is ...
5
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1answer
350 views

How to convert a column of numeric IDs to letters?

I'm working with qgis 1.8.0. I divided a map into 500 features (small rectangles), and now I have the doubt if there is any way to change the ID of the attributes from numbers to letters? When I did ...
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105 views

How to add a field to a .zip shapefile?

I am exploring the possibility of using ArcGIS Online (Free Public Account and Explorer) with my new Global Studies students. (So far, the Free Public Account appears to be more user friendly and ...
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1answer
515 views

Connect not working for custom QGIS form

So I have a custom form for editting feature attributes. However, I can't seem to correctly disconnect and reconnect certain bindings. The init code is below and should work for any simple QT widget ...
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1answer
455 views

Qgis crash when I attempt to open ECW raster format.

I added Ubuntugis unstable repo and installed Qgis, libgdal-ecw-src, libecwj2-3.3 but still do not work. When I attempt to open an ecw file with Qgis it crash and tells me that there are problems ...
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1answer
153 views

QGIS Spatial Queries

I was wondering if I could do the following within QGIS: I want to update a column in my point layer with the attribute information from a specific column in a polygon layer - so I have a layer of ...
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37 views

QGIS Render shape when partially of screen

I am rendering a census area, a polygon the source of which is kmz file. THe shape only renders when the entire extent is visible on the screen. If I zoom in so some of the polygon extent is off ...
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0answers
75 views

QGIS Gazetteer Plugin connection to internal database

A few posts on here mention that the Astun QGIS-Gazetteer-Plugin could be adapted to reference a PostGIS database. Has anyone done this adaptation and could share it? I want to use a gazetteer stored ...
2
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1answer
89 views

cannot download 3rd party plugins in qgis

I want to download SDA4PP plug-in in QGIS. Unfortunately I cannot see the button to download 3rd party plugins, as indicated in the install instructions at that link. I am using this program on a ...
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2answers
589 views

Openlayers Plugin, Project CRS and Grids in Composer

Apologies in advance for the potential for this to be a duplicate question, I've had a good look, and I can't see a solution thatI understand well enough to help me. I have my project CRS set to a ...
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1answer
79 views

point shape file problem

I have a point shapefile which was created from a text file in Excel using the delimited text layer plugin in QGIS. My problem is that I am getting a point shapefile but when i try to insert this in ...
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1answer
31 views

Why do I suddenly get 'ERROR' as elements in my attribute table after doing a query in QGIS?

I was looking at an .osm file in QGIS using the OSM plugin; I was specifically looking at a country's lines layer. When I checked the attribute table just after opening the .osm, everything looked ...
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1answer
75 views

How does one install QGIS from previously downloaded OSGeo packages

I have downloaded the OSGeo Installer (on Windows 7 x64) and run it, selecting the Desktop Express Install option. All of the files were downloaded and the installer reported a successful install, ...
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1answer
5k views

How do Qt Designer and QGIS work together?

I am just trying understand how qgis and designer work together. From Nathan W's excellent posts I know how to create a user form and how to hook it to a qgis layer and also how to add validation ...
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62 views

QGIS: (Shapefile) Convert rings to fake-rings?

I hope I can make my question I posted yesterday clearer... sorry! Basically, I want to obtain the opposite of this: How to convert fake donut holes in polygons to real ones? Such polygons will ...
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2answers
555 views

How to extract features with specific coordinates from a ShapeFile?

I would like to extract a number of features from a ShapeFile which match with specific latitude/longitude values. I am interested if/how this can be done with QGIS and ogr2ogr. The output should be ...