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

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558 views

How to fix “Connection failed - Check settings and try again” when connecting to PostGIS?

I have Postgres running via Postgres.app on rails already and am trying to connect QGis to the database. PostGIS is working already. (questions already found online deal with this issue only) I do ...
2
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1answer
135 views

How to convert a line to points?

I'm working with QGIS and I want to convert a line into many points, does someone know how? Thanks.
2
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1answer
146 views

Where can I find the data that QGIS used to custom its menus as well as it's toolbars?

I have noted that QGIS uses some data to restore its menuitems as well as its toolbar items everytime when it is started.And I have being trying to hunt them out in my hard disks but sadly ...
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1answer
145 views

How to merge polygons into a single item where an attribute is same?

I have a shapefile of a area .It consists of list of fields in which sub locality is also a field.Under the sub locality field all the areas are common say for example: perungudi,perungudi,perungudi. ...
2
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1answer
588 views

How to create a QGIS Action which loads a raster?

I am following an article here:Actions HowTo , specifically the piece about an action to load a raster: Python type Add Raster Layer ...
2
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2answers
268 views

Import Points with WKB format to QGIS

I have a .csv file with population data according to specific locations (Points). My problem is that all locations are given in WKB format like that: ...
4
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0answers
66 views

What's the best way to add Tilemaps to QGIS without having to use Webmercator? [closed]

I'm looking for a good way to add tilemaps in qgis that are either in a custom projection or that I can reproject in qgis. I have used the openlayers plugin to add basemap layers, but it forces me to ...
1
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0answers
70 views

How can I maintain MapInfo GRC file attributes in QGIS/GDAL?

I am trying to manage a classified MapInfo grid file in QGIS - I'm wondering if anyone has any experience with maintaining the attributes of the classified grid? QGIS seems to assign them just a ...
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0answers
222 views

Shapefile projection issue - layers not lining up [closed]

See below for screenshot. The purple rectangle should line up with the green rectangle in the top right (OpenLayers Google Physical layer) and the tan points. I was sent this shp and given the ...
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1answer
49 views

How to set layer symbol and layer name side by side in QGIS Composer?

When I add a legend in QGIS Composer, the layer symbols are set below each layer name. Is there any way to have them side by side? This is what I get: "LayerName" [layer name] ~ [layer ...
7
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2answers
355 views

Is there an open source alternative to ArcGIS for Desktop's Integrate tool?

I need to snap about 1000 lines in one layer to the lines in another layer (there are about 5000 lines in the second layer). The lines to be snapped are about 15 map units away from the base layer ...
3
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2answers
385 views

Is it possible to embed QGIS layer styles in a Spatialite database?

Spatialite is a great alternative to shapefiles - but how could I store the QGIS layer style together with the data so that it has a default style? For a shapefile I would just save a [name].qml with ...
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1answer
109 views

How to Resize the Qgis Main Window from python

I would like to write a plugin that simply resizes the qgis main window to make it small. How can I access the qgis main window through the qgis api? Use Case: We are having problems with qgis taking ...
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2answers
293 views

How to add a dynamic timeline to the QGIS canvas?

I am using the plugin Timemanager which works really great but there is one thing I'd like to improve. Instead of displaying the date and time on each frame, I would like to display a timeline ...
0
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1answer
253 views

How to convert OSM polyline data to polygons?

I just now downloaded OSM data .I am having the data as polylines. I want that polylines as polygons is it possible in Qgis?below I also posted the screen shot of the polyline also.
2
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1answer
458 views

Can Tiff files from ESRI Geodatabase be loaded into QGIS

I have been able to load an ESRI geodatabase which contains shape files into QGIS, however when I try to load a geodatabase containing tiff files I get an error message saying ...."is not a valid or ...
0
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1answer
133 views

eVis-Plugin centers mapwindow on coordinate origin

I have a QGIS-project with layers loaded from a postgis-database and also some shapefiles. I use the eVis-Plugin to display pictures. The displaying is working fine but after clicking on the geometry ...
3
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1answer
106 views

Field Value Mapping QGIS

I am wondering if there is a way to do field value maps that are filtered based on another attribute field? I know how to associate value maps, but not that are connected to another field. I have ...
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1answer
581 views

How to count number of polygons inside another polygon layer?

I am looking for a tool in arcgis 10.1 Qgis or R that allows me to count the number of polygons that are inside specific areas (defined also as polygons). My data consists in: 1 shape file with ...
2
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1answer
147 views

Is there any way to find the shortest distance from a point to a line?

I´m working with QGIS 1.8.0. I have a map divided into many features (thousands of small rectangles) and I have a point at the center of each of those features. I also have a map of the transmission ...
2
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0answers
177 views

How to handle crashes on save causing “Project file read error: unexpected end of file at line 1 column 1 for file [pathway]”?

QGIS 1.8.0 Tried to save a project and as I saved it gave me the "QGIS has experienced an error and needs to close" Next time I went to open the project I got this (well I was going to post an image ...
3
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1answer
57 views

Does Quantum GIS recognize QDGC information?

Good morning! So a bit of background on what I am working on: We are in the process of assisting a wildlife institution in South Africa with trying to take their information and surfacing it in a ...
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1answer
102 views

How to write a QGIS Action which opens a PDF from a server?

I need to open a PDF from an action in QGis. The PDF rests on a server, not local. So far I tried this (as Python): from PyQt4.QtCore import QUrl; from PyQt4.QtWebKit import QWebView; myWV = ...
0
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1answer
164 views

How to convert a .rik to .tif?

I have a quite large high-resolution map in a format called .rik from the Swedish land survey agency. I want that whole high resolution file in different format that can be used to print a map from a ...
2
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2answers
316 views

Is the derived area/length/xy values of a polygon/polyline layer in QGIS usable?

I have a raster that is projected to a state plane CRS and I am adding polygon/polyline shapefiles that are projected to WGS84. On the fly transformation is set to reproject to my raster CRS. When I ...
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4answers
161 views

What units are my coordinates in?

I opened a georeferenced NAIP photo to a new project in QGIS. The coordinates were expressed as: 2199240.6, 616858.7. The same point in Google Earth was expressed in degrees, minutes, seconds, as ...
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1answer
91 views

How can I create a basemap from an NAIP image using QGIS? [closed]

I unzipped the image and loaded it in QGIS as a raster. Now, how can I turn that image file into a basemap that lines up with a specific coordinate system?
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3answers
90 views

How can I create a simple basemap in QGIS that will allow me to trace a polygon with an accurate projection?

I need to find an aerial photograph, create a new vector layer, trace several fields in this aerial photograph, and find random coordinates within these polygons. I first tried this with the Google ...
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0answers
66 views

How to change API version from 9.0 to 8.1 to load PyGIS

Traceback (most recent call last): File "", line 1, in RuntimeError: the sip module implements API v9.0 to v9.2 but the qgis.core module requires API v8.1
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0answers
40 views

Why does exported map from print composer differ from map canvas? QGIS 1.8.0 [duplicate]

I have a small project consisting of a Google maps satellite open layer with two new shapefiles overlaid on it. I have then used print composer to add a grid and some labels. I have also selected lock ...
3
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0answers
154 views

QGIS does not read ESRI Geodatabase correctly

I have a geodatabase from the EPA that does not seem to me reading correctly with Quantum GIS. When I open the attribute table the first two columns have the same data. The first column is CERCLA_ID ...
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2answers
141 views

Is it possible to change CRS without the .prj file?

I'm working with QGIS and trying to change the CRS of some maps. Is is possible to do it without the .prj file? Please let me know. Thanks.
2
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0answers
59 views

Loading a layer into the same position as an existing layer in QGIS

I understand that it is not possible to directly reload a shapefile layer in QGIS using the reload method in Python, since this method is not implemented for shapefile data providers. Thus, the ...
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1answer
124 views

How to divide a shapefile in QGIS

German original: ich beschäfte mich gerade mit QGIS. Ich habe über die Funktion mein Shapefile hinein geladen. Jetzt ist mein Problem: In dem Shapefile sind unterschiedliche Punkte, wie Punkte für ...
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0answers
152 views

Sources for German Standardized Symbols in QGIS

German Original: Gibt es für QGIS eine Phytonerweiterung "Planzeichenverordnung"? Zur Bearbeitung von Flächennutzungsplänen und Bebauungsplänen kommt man an den Planzeichen nicht herum. ...
1
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1answer
293 views

Import GPS data (text documents files) to QGis

I want to import GPS data (text document files) in to Qgis, what file format are you suppose to use ?
2
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1answer
151 views

Change Values of Georeferenced Raster

I am using QGIS to georeference B&W images. I have now done this and would like to set the black surround of the image (as a result of the georeferencing) to transparent but this does not work as ...
3
votes
3answers
514 views

Is there a Raster Equivalent of the Split tool?

I have the DEM of a State in ERDAS Imagine (.img) format. I have a shapefile containing the counties of that state. I want to split the whole raster into DEMs of the individual counties. The counties ...
1
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4answers
1k views

Python Error Message with OpenLayer Plugin

I have just recently downloaded QGIS version 1.9.90-Alpha, Alpha, 5155176. I then went to install the OpenLayers plugin. That successfully downloaded and installed, or so I thought, but when I went ...
2
votes
4answers
643 views

Unable to load GRASS plugin

I upgraded from QGIS 1.7.0 to 1.8.0, including updating GRASS to version 6.4.3. Since then, GRASS isn't any longer listed in the Fetch Python plugins. I uninstalled and re-installed the whole package ...
1
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1answer
651 views

Using Landsat 8 for quantitative analysis - what DNs does GRASS require?

Hoping someone can short circuit a lot of exploration Landsat 8 values are stored as unint16 since the sensors work on a range 0 to 4096 whereas the L7+TM was 8 bit and had a digital number range 0 ...
2
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2answers
2k views

Exporting shapefile to PostGIS database in QGIS

How do I export a vector shapefile to PostGIS database? I am asking what format I have to export it.
0
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1answer
68 views

how to select parts of a shape in QGIS

I have to have a Shapefile of France of the bigger regions: Ile-de-France, Bretagne, etc. and that is already included in my shape. But its only shown the Arrondissements (smaller regions) in France ...
0
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2answers
103 views

Attribute Table Doubt in Qgis

I am having a shape file which consists of various fields for example: shape area ,shape length, locality, sub-locality,district etc.In my company they are demanding seprate shapefiles say for example ...
3
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0answers
190 views

Create a path following a road, interpolating from a set of points

I have several hundred vehicular routes within a city from which I wish to create shapefiles. These take the form of directions such as "From Green Street, turn left into Brown Street, Right into ...
2
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1answer
87 views

Revert back from RGBA raster to original 1 band raster cell value

I have a number or single band raster grids that have been converted to RGBA (png). I no longer have access to the orignal single band raster data but have the png files. Is there a way to convert the ...
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0answers
52 views

QGIS: georeferencing report: tail cutted off

I'm using QGIS 1.8.0-2 to georeference some old maps and want to report residuals and other information via the PDF report function of the Georeferencer tool. If there's too much information, it's cut ...
0
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1answer
49 views

How can I use a tif and a SID to make a basemap in QGIS?

I am trying to add a basemap in QGIS, projected correctly for PA. I have been directed to PASDA. When I click on the FTP download link, it gives me the option to download TIF data or SID data. What ...
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2answers
240 views

Customise the splash image of QGIS

Where can I find the splash image which is shown while starting QGIS, and how to customise it?
3
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2answers
437 views

How to do a Point to Polygon analysis with multiple variables?

I have a database of almost 10k crimes, which are divided in to 10 categories and plotted on a map I also have a database of 12k addresses, which are also plotted on the map. I aim to perform a ...