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

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1answer
153 views

When I join a table to a shapefile and then export it the titles of the columns are transformed to data1, data2

I'm using QGIS 2.0.1 The table is in an excel format that i import through "add vector" and the shapefile is a polygone I join the attributes by right clicking the polygone-->properties-->join Then ...
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0answers
198 views

QGIS plug-in equivalent of ArcGIS's Spatial Analyst Tools -> Overlay/ Weighted Overlay

Specifically I have 12 .bil raster files that show monthly global mean minimum temperature. I file for each month. I want to combine these to create an ANNUAL global mean minimum temperature. In Arc I ...
0
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1answer
73 views

QGIS Legend horizontal not vertical

Hi is there an easy way to have the legend linked to the size of the box it is drawn in. So instead of running down the side of the page, it will be across the bottom in columns? Does that make ...
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2answers
281 views

Union in QGIS: missing polygon boundaries

I am trying to UNION two shapefiles in qgis. I use the geoprossesing tool UNION. Both sf are in the same coordinate system (same as in the project). In the resulting sf some polygon borders are ...
2
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3answers
551 views

Draw line between points from multiple datasets

I have 2 point datasets and want a tool or script to draw a line between all points in one dataset to all the points in the 2nd dataset. Is it possible? I have tried ESRI "Point Distance" and ...
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2answers
2k views

QGIS select features from attribute table using the “LIKE” operator

I created an expression with the help of the GUI in the QGIS attribute table of a vector (shapefile) layer of Native American ("Indian") reservations in the USA state of New Mexico. "NAME" LIKE ...
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0answers
27 views

Show the paths but not roadsides and driveways in the line layer

I want to display paths in the woods but the paths are all in One (line) layer that contains all roadsides, pavements, drivvays, but also paths, tractor road and other relevant roads in, and up to the ...
2
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1answer
381 views

Change contour line stroke weight based on elevation?

I have shapefiles of contour lines that I have imported in Qgis. At the moment the contour lines are all the same stroke weight. I'm a beginner to this program, but wanted to know if its possible to ...
3
votes
1answer
252 views

Exporting a QGIS layout with Addition on layers

I've been playing around with an approach in QGIS that uses Addition between the layers I'm mapping to build a tri-variate composite colour map - an example is here in the QGIS Flickr pool: ...
1
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1answer
152 views

Why can't QGIS open my KML file? [closed]

I have a kml file with multiple absolutely identical polygons but with different names. I need to load it to qgis and find points in these polygons. But I guess qgis thinks that multiple duplicated ...
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0answers
65 views

QGIS crashes when digitizing new fetaures

I can't currently digitize polygon features in QGIS 2.01 or 2.3. I can draw a set of points but as soon as I right click to finish the system crashes. It still works fine in 1.8. Windows 7 64
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1answer
332 views

QGIS Quickly switching overlapping raster images

I'm new to QGIS, and haven't used arcGIS in about 5 years, however I've just seen someone using arcGIS and was able to quickly switch between overlapping rasters when checking registration. The top ...
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2answers
178 views

Interpolation using GRASS plugin in QGIS

I have been using the IDW interpolation tool through GRASS plugin in QGIS and the interpolation output I am getting is for the entire mapset region. My question is: Is there a possibiltity that we ...
0
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1answer
278 views

Merging Raster: ImportError: No module named _gdal_array

When I try to merge rasters I got following error message: _gdal_array = swig_import_helper() File "C:\PROGRA~1\QGISDU~1\apps\Python27\lib\site-packages\osgeo\gdal_array.py", line 18, in ...
8
votes
5answers
369 views

Print out the properties of the attribute table in qgis?

I have to merge a lot of shapefiles into one great shapefile. So I want to compare the properties of the attribute tables to see if there are differences between the tableproperties of each shape ...
0
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1answer
201 views

Using GRASS plugin tools from OSGEO4W command line

I am trying to do the interpolation of GRASS vector shapefiles using GRASS plugin tools. My objective is to run interpolation tool in GRASS plugin from OSGEO4W command line, which will help me ...
1
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1answer
431 views

Floating point calculations in QGIS

How do I manage floating point calculations in QGIS? I have carried out 3 consecutive calculations on landsat bands. I end up with 32 bit floating point rasters on which I can't carry out a 4th ...
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0answers
174 views

How to create a new table with point geometry column using QGIS DB Manager?

I have been trying to use QGIS DB Manager to create an empty table (QGIS 2.0 on Win7). My hope is that I can make an empty point file and use it to add data to, via heads-up digitizing (like you ...
1
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1answer
181 views

Maximum scale dependent visibility changes from 1:0 to -2147483648:1

QGIS 2.0.1 Dufour. When i open the layer properties and the scale dependent visibility is unchecked and when i check it, the maximum (inclusive) shows 1:0. I click Apply, OK, reopen layer properties ...
3
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0answers
129 views

How to fetch openlayers layers from pyqgis? [duplicate]

My objective is to fetch maps provided by openLayers, as in openLayers_plugin, from a stand alone python script. I would like to get it superposed to my shp file. As can be read on ...
0
votes
1answer
110 views

Can QGIS report/calculate areas/perimeters of individual polygon components within multipart shapefile?

Can QGIS report/calculate the areas/perimeters of individual polygon components within a multipart shapefile without using the "explode" vector tool to generate a new file? using QGIS 2.2.0 on ...
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2answers
395 views

Breaklines in QGIS interpolation plugin

How can I prepare data to generate a DTM using points and breaklines, but where every breakline has nodes at different heights. For example, a river valley, which regularly falls, or a dorsal line, ...
2
votes
2answers
1k views

How do I open images georeferenced in ArcMap in QGIS? (.aux.xml)

We have several ArcMap georeferenced images (raster datasets) that we are attempting to open in QGIS without any luck. These are not inside of a geodatabase and are not Arcinfo Binary Grid format or ...
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0answers
25 views

QGIS - unable to change projections [duplicate]

I am relatively new to QGIS (version! 2.0.1) and having trouble changing projections. No matter what I choose the view is the same. For example, in the attached screen shot I have chosen Alaska Albers ...
3
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1answer
139 views

Re-registering a GEOTIFF in qgis

I'm working on some images taken from a UAV over the course of a year. They are OSGB 1936 projection as is the whole project. Annoyingly they don't quite line up so I am trying to a few of the images ...
3
votes
1answer
260 views

Where is qgis getting the NO DATA value from?

I have a project that contains an 8-bit paletted layer (call it the mask layer) and a float 32 single band layer (call this the clip layer). I create a new raster by using the raster calculator, ...
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0answers
54 views

Error running SEXTANTE in QGIS on Scientific Linux

I've installed SEXTANTE into qgis on my Scientific Linux machine and I am getting the following when attempting to run Warp; INFO|Mon Feb 24 2014 15:56:20|GDAL execution console output|/bin/sh: ...
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0answers
62 views

How to get the signal when the color changes in pyQGIS?

I would like to have the signal when the color of a vector layer is changed by the user. In the doc, there is a signal that seems to fit ...
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0answers
51 views

“System not initialized. Programmer forgot to call G_gisinit().” message when loading table into GRASS via QGis

I am trying to load a CSV table into Grass with v.in.asciifrom the interface of Qgis 2.0.1 on Windows XP. As the progress bar indicated 74% of the data already loaded, I got the message "System not ...
3
votes
1answer
302 views

Qgis 2.2 how to fix bad epsg.wkt load

I installed Qgis 2.2 this morning from the ubuntugis repository for ubuntu precise. Qgis works great, except that all the common projections have been deleted. So, I am a Little bit having a heart ...
7
votes
2answers
1k views

How to configure QGIS and SAGA on Ubuntu (12.04 and others)?

During the past weeks, I have tried QGIS to recognize SAGA via the processing toolbox, both being installed from the ubuntugis-unstable repository. I have tried this on several virtual ubuntu ...
2
votes
1answer
37 views

Wrong sorting of elevation classes QGIS

I'm a totally beginner with QGIS and maybe I have a very easy problem, but I can't help myself. I got an elevation shapefile with classes of elevations like that: 1-100m, 101-200m, ... When I try to ...
3
votes
2answers
2k views

QGIS GISBASE specify location

I am just a beginner at this QGIS and GRASS and I am using this QGIS 2.0.1 Dufour which throws a error at the startup that "QGIS couldn't find your GRASS installation. Would you like to ...
2
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0answers
103 views

How to Simulate Venn Diagram of Buffers using QGIS?

For the sake of simplicity, suppose I have only 2 points on one layer. Point A have population of 100, and point B have population of 150. I do find buffer of these 2 points and it is intersect. I ...
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0answers
208 views

how to add polylines(routes from public transport) on postgresql(pgrouting) with GUI

After searching a several long time... i decide to ask here for help, im currently using ubuntu 12.04(because of compatibility) with postgresql 9.1, postgis2, pgrouting2 and qgis2.2 i need ...
3
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0answers
689 views

Move Scale Rotate raster in Qgis

I have some archaeological scanned raster that they have a north arrow and a scale bar. There is no grid, no coordinate system.I would like to put those files in a general map. I don't care about the ...
2
votes
2answers
401 views

How to write a new layer to PostgreSQL from QGIS plugin

The PyQGIS cookbook states that QgsVectorFileWriter can write vector layers to any format supported by OGR: https://www.qgis.org/en/docs/pyqgis_developer_cookbook/vector.html#writing-vector-layers ...
1
vote
1answer
173 views

Can I automatically save datetime for every entry in my spatialite tabel? [duplicate]

I'm using QGis and SaptiaLite. Is it pssible to store date and time in a field "datetime" for every entry automatically - maybe with some python code? Already existing datetime should not be updated. ...
1
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2answers
269 views

How can I centralize QGIS connections for multiple QGIS installations

I have multiple computers with QGIS installed on them. I regularly use the same WMS / WFS services. Now I have to connect to these services for each QGIS installation separately. It would be great ...
0
votes
1answer
134 views

v.edit break: how to loop through XY coordinates on using GRASS on Windows 7

Trying to follow the suggestions on this thread: splitting a lines layer using points However, how to do so in a windows environment using the GRASS command console is beyond me, so I'm attempting ...
2
votes
4answers
512 views

How to turn all lines into one direction?

How can I turn all features of my polyline (postgis and/or shapefile) into one direction - it doesn't matter what direction. I know how to switch the direction of lines but I have no idea how to ...
2
votes
2answers
254 views

Open Arabic Shapefile in Qgis

I have a shape-file all it's fields are in Arabic. When I opens it in qgis 2.0 all the data is replaced by "?". I changed the encoding to Arabic or UTF-8 but with the same result. How can I Open an ...
1
vote
1answer
125 views

Why do features in QGIS drawn on same datum as Google imagery from OpenLayers move? [duplicate]

I have just started using QGIS. I've loaded the "openlayers" plugin and added a google hybrid layer, which is based off the WGS84 datum to my understanding. Now I create a shapefile and add a new line ...
2
votes
1answer
235 views

Is there a limit to the amount of data in a spatial join in QGIS?

I am using Quantum GIS and trying to spatially join a point grid with polygons that are overlapping. If I get the sum of intersecting features, then I can get a good raster value. Well, every time I ...
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0answers
69 views

Zonal statistics won't work after re-projecting vector layer

I have qgis 2.0. I want to analyze raster information within a buffer of 30 miles around a vector layer of cities across the world. However, both the raster and the vector are in WGS84. I have no ...
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2answers
324 views

QGIS Installation - Oracle Link

Trying to connect an oracle 10g database to QGIS. I'm getting the error below: ORA - 12154: TNS:Could not resolve the connect identifier specified Anybody ever seen this error, or could provide some ...
2
votes
1answer
294 views

Calculate distances between polygon centres in QGIS

Is there a practical way to calculate distances between polygon centroids in QGIS? I have a UK city region map divided into administrative units (1 ward = 1 polygon). I want to represent their ...
3
votes
2answers
625 views

How to produce a CSV file from .tif file with elevation data? [duplicate]

just want to ask, I have a .tif file that contains all the elevation of a country. How can I convert that to a CSV file that contains x,y,z values where x and y are the latitude longitude respectively ...
1
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2answers
59 views

QGIS 2.0 How can i get a precisely Rendering time?

I work with QGIS 2.0.1. I have a large number of raster data files and i selected different methods to represent them. Method: Import all raster data as individual files Method: Generate a single ...
3
votes
1answer
439 views

Plugin Tutorial issue: trying to work around changes in QGIS API

I'm currently following the tutorial to create my first python plugin for QGIS: http://www.qgisworkshop.org/html/workshop/plugins_tutorial.html and have similar issues to this thread: QGIS 2.0 Plugin: ...