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

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1answer
121 views

Scaling location points proportionately

I'm trying to get QGIS (1.8) to scale the point markers for each town in a district proportionately to the size of their population (i.e. bigger population = bigger circle). I can get them to vary by ...
5
votes
1answer
140 views

What suit of components do I need to get installed to start with QGIS?

I have a requirement for a GIS product and following advice from firends and colleagues have decided that Quantum GIS seems suitable for what I need. I have input a request to our IT section to ...
3
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2answers
1k views

Are there any work-arounds for WMS width and height limit when printing?

I get the following error when trying to export in QGIS to PDF: "Some WMS servers (e.g. UMN mapserver) have a limit for the WIDTH and HEIGHT parameter. Printing layers from such servers may exceed ...
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2answers
830 views

Error adding a delimited text layer in QGIS [closed]

I'm a GIS beginner here. I'm trying to add a delimited text layer in QGIS. The plug-in is okay. I have created a table in Excel, saved as CSV file, imported the file with QGIS, selected the delimiters ...
1
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1answer
602 views

What are Bands, Dimensions, and Histograms in QGIS?

First; I can see a band as synonymous with a channel in an image editing program like GIMP, is this correct? If so then bands play the role of color mixing and masking. Are there any other ...
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0answers
30 views

Why does my QGIS want to create so many icons? [duplicate]

Not sure on protocol here--I asked this previously, but the responses petered out-- Every time I open a Print Composer, a box comes up, and text flashes by saying, "Creating icon for file [various ...
2
votes
1answer
243 views

Sum line length with clip intersect? [closed]

SELECT sum(st_length(st_intersection(POLY.geom, LINE.geom))) AS sum_line_length... Is this function OK to calculate the sum of lines length? Wonder if it do the clip line where one line go from one ...
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1answer
354 views

Cannot install TimeManager 0.7: no module named six

I was able to extract and copy dateutil to C:\OSGeo4W\apps\qgis\python\dateutil and the error saying that dateutil wasn't found disappeared. But now I am getting the error no module named six. Tried ...
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2answers
432 views

QGIS rounds up the coordinates to six decimals when saving layer changes

I have the problem that when I create a new point (in a point layer) or a new line (in a line layer of course) and I save the changes to the layer (so NOT the project save) then QGIS rounds up the ...
3
votes
1answer
88 views

What defines a Class in the Heat map plugin?

What defines a Class in the Heat map plugin? As in: "Black holes like that are usually caused by raster values exceeding the range of the color ramp. Try adding another class with a higher associated ...
2
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1answer
54 views

How to make a certain attribute Toggelable? [duplicate]

I have imported data from an excel spreadsheet containing lat,long coordinates associated with other attributes such as current operator of each point (well). I imported as a tab delimited file, then ...
14
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3answers
5k views

How to snap lines to points automatically?

I have two vector shapefiles: One file is points representing manholes and the other is a polyline file representing pipes leading to and from the manholes. I need to snap the lines within a ...
3
votes
1answer
2k views

How to convert jpg file to shapefile? [duplicate]

I am developing a GIS application like this: By now my steps are: I have got a jpg file, 5040 x 8179 dimension. In this map, the roads, rivers, towns etc. are marked. I am using .Net to develop ...
1
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1answer
418 views

Find closest point from origin in QGIS and display measure line in composer

I have a location point. there are several constraints areas surrounding the point. Is there a way to calculate the closest point of this constraint from my point and to display the distances as a ...
6
votes
2answers
1k views

How to implement multivariate hex bins?

I have two point datasets that I am analyzing and I wanted to implement a multivariate hexbin approach for displaying this data. I have managed to cobble together an approach using QGIS SVG symbols ...
3
votes
1answer
939 views

QGIS Print Composer Export problems

When I attempt to “Export as PDF” a Print Composer image, it hangs up until I press cntrl/alt/del, whereupon I learn that QGIS is not responding and needs to be closed. I’ve tried this as jpg, jpeg, ...
0
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1answer
93 views

gdal_contour creates an empty shapefile

I am running: gdal_contour -a elev hazard_interp4.asc haz_ak_contour_4_10 -i 10 the hazard_interp4.asc file has values in band 1 (singel band gray). With the above command, I get a shapefile that ...
5
votes
1answer
150 views

Automatically build branches of a river network?

A small non-profit specializing in fish habitat restoration, has asked me to link a spreadsheet of field notes to their GIS. What we have is: A spreadsheet of field notes for small fish streams. A ...
1
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0answers
210 views

Heat Map trouble: Is this a data formating problem?

I'm playing with the heat map plugin with QGIS. I've run through QGIS tutorial: http://docs.qgis.org/html/en/docs/user_manual/plugins/plugins_heatmap.html, using the airports data set as explained ...
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0answers
302 views

GeoTiff.lib: TiePoints only without ModelPixelScale do not get georeferenced in QGis

I have an image that has been georeferenced (geotiff.lib) by more than 3 tie points (x y 0 long lat 0 ...) and added following geotiff keys GTIFKeySet(gtif, GTModelTypeGeoKey, TYPE_SHORT, 1, ...
3
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0answers
158 views

How does Zonal statistics handle pixels that are on the border of the polygon?

I am using the plugin zonal statistics to calculate the sum of the raster cells within polygons. How does this plugin handle pixels that are on the border of the polygon, are those cell values ...
4
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2answers
138 views

One of my ID numbers for my polygon is not being shown when I label my layer. How do i fix it?

I have 20 polygons and when I tried to label the layer with the ID numbers only 19 appeared. For some reason my first polygons ID number is not being shown and I dont know why. Am I missing something ...
0
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0answers
438 views

How to upgrade from QGIS 1.4 to 1.8 on Linux Mint 12?

I've been trying to upgrade from the Enceladus 1.4 version of QGIS to 1.8 on a Thinkpad T42 running on Mint 12. When I try to upgrade from within QGIS help menu I receive the following error message: ...
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1answer
125 views

Problem loading raster to PostGIS using QGIS

I am having trouble loading a raster (.asc) file to PostGIS 2.0.1 using the plugin Database - PostGIS Raster - Load raster to postgis in QGIS 1.8.0 on Win Vista 64 bit. I get the following error ...
0
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1answer
313 views

gdalwarp cant find libproj.dlib

Thought I had finally got Python, gdal and QGIS to play nicely together but just tried to do a batch transform using a bash script to call gdalwarp and it claimed it couldn't read the libproj.dlib ...
2
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1answer
430 views

How to realign (PostGIS) layers in QGIS?

I'm trying to realign layers in QGIS. As you can see here, the "background" light-blue layer is not aligned with the top layers. I'm working with pgAdmin III and importing PostGIS Layers in QGIS. My ...
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4answers
3k views

Free Imagery WMS Feeds in QGIS

I was wondering if anyone knows of a free WMS of imagery that I could use within QGIS. The imagery does not have to be high resolution (Blue Marble even). I would like to have a base imagery feed ...
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0answers
68 views

When digitizing, objects are not saved well

I've some problems with digitizing. If I draw a line or a polygon, the line or polygon is saved in the attribute list, but not visible and its location is not saved either (when I zoom to the object ...
4
votes
4answers
567 views

How can I create polygons of the area surrounded by roads / lines?

I'm currently trying to create polygons that represent the areas surrounded by roads. The roads are stored in PostGIS as points / lines so I have flexibility over what I can do with them. I'm ...
1
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0answers
681 views

Distance Matrix in QGIS

Can anyone help me with the distance matrix tool in QGIS? Is there a tutorial about it? It sometimes crashes when I use it and the values that it produces seem strange. I am a beginner in QGIS, so I ...
5
votes
1answer
2k views

How to convert coordinates in a .csv into another CRS in QGIS

How can I convert coordinates which are stored in a csv and in a certain format in a different CRS, i. e. I want to convert GK 3 (EPSG:31467) into WGS 84 (EPSG:4326). I am using QGIS and already ...
2
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0answers
186 views

how to intersect a raster subset with a buffered vector layer (points) in QGIS?

I am a bit new in the GIS and qGIs sphere so maybe my question will look a bit naive, but at the same time it means it should probably be easy for most of you guys ;-) I work in QGIS.I have 2 layers: ...
1
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1answer
257 views

Qgis - Raster clip Problem

I tried to use the Raster (Extration) tool "clipper" and I always get this error log: What is my problem? Fehler bei der Ausführung von Python-Code: Traceback (most recent call last): File ...
1
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3answers
961 views

Is there a way to get correctly aligned print export with openlayers plugin? [duplicate]

I am a beginner using QGIS (1.8.0 Lisboa) on a Mac (OS X 10.6.8 Snow Leopard). I work on a file with two layers in the following sequence (top to bottom): a vector polygon layer with a few outlines ...
3
votes
1answer
2k views

How to convert shapefile to vector emf?

I want to convert a shapefile to an EMF file. The EMF file must be a vector image, not a raster image. Please suggest to me some good packages or tools. Thanks in advance.
3
votes
1answer
255 views

Why is my Polygon (WGS84) in SpatiaLite 4 not displayed by QGIS? [closed]

I made a polygon in a SpatiaLite 4 database as follows: INSERT INTO test_pg (id, name, geom) VALUES (3, 'test', ST_PolyFromText('POLYGON((8.556824 47.185269, 8.611009 47.185269, 8.611009 47.218568, ...
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1answer
72 views

Why does Print Composer take ages “Creating icon for file …”?

Every time I open a Print Composer, a box comes up, and text flashes by saying, "Creating icon for file [various random image files that I have on my computer]". It then pauses, and does it again, and ...
1
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1answer
284 views

Which horizontal unit is used on the table of the Profile Tool?

Does anyone knows what horizontal unit is used on the table of the "Profile Tool". Vertical is in meter but I don't know about the horizontal axis. Knowing the length of my profile, I tried to divide ...
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0answers
93 views

How can I snap 2 lines in QGIS so the st_distance between them is 0?

Sometimes when I snap the ends of 2 LineStrings together and I check the st_distance between those endpoints I get a value in the order of 1.1E-10 while at the same time when I check for equality of ...
0
votes
0answers
240 views

Does Polygonize in QGIS 1.8.0 work correctly?

Does anyone else have issues with the Polygonize function in QGIS 1.8.0. When i use it is to extract details from larger raster images, through raster calculator, then polygonizing the resultant ...
2
votes
1answer
2k views

QGIS Python version

I have brewed python 2.7.3 onto my Mac (Lion), and installed shapely via pip install shapely. The Polygonizer plugin, however, does not find the shapely library. I see when QGIS loads a Python ...
2
votes
3answers
3k views

Joining attributes of polygons and points by location in QGIS

I have two shapefiles.... points containing a number field 'response_time' a polygon grid of square polygons containing fields including 'PNTCNT' with the number of points per polygon, calculated ...
5
votes
2answers
283 views

How to include streaming media into an OpenGeo system to monitor live-tracked animals?

I am wondering how to include streaming media (video), or camera feeds, into an OpenGeo system to monitor live-tracked animals. I am currently doing so with different applications, but I want to do ...
0
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1answer
396 views

Does QGIS support vector Rubbersheeting? [duplicate]

The task is to rubbersheet two vector layers one with a projection like UTM WGS 84 Zone 45N
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0answers
53 views

Spatial adjustment for vector shp files in QGIS [duplicate]

How to do spatial adjustment for vector shp files in QGIS? I have a set of 4 cadastral maps of adjacent locations. I have converted them form DWG to DXF and then to vector shapefiles. They are not ...
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2answers
621 views

How to use a hillshade dataset in QGIS?

I received “Hillshade” data that I'm trying to use in QGIS. When I check the "Pseudocolor" option under "Color map", I get many colors, apparently corresponding to the terrain, though it doesn't ...
2
votes
1answer
171 views

How to symbolize points using line symbols of varying rotation and width?

I've been along a stretch of coast and recorded the orientation and thickness and locations of several igneous intrusions. I've managed to set up a project in QGIS with a point for each intrusion, ...
1
vote
4answers
860 views

Why does QGIS not detect the CSV/DBF column headers?

I am trying to import a csv or dbf into qGIS so I can perform a join on a shapefile. However, qGIS is not detecting the first row as header names. I know I've done similar joins before and there's ...
2
votes
2answers
204 views

How can I import ALOHA .pas plume file into QGIS?

I am trying to find a way to import ALOHA's plume model (.PAS) into QGIS? I have not been able to find anything showing how to accomplish this outside of using ESRI-based tools.
0
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1answer
334 views

Is it Possible to Convert a GRD File into an ASC File in QGIS?

Is it possible to convert in QGIS a GRD file (that was created in MapInfo) into an ASC file (that can be imported into SAGA)? Is it possible to "extract by mask" a section of a GRD file in an other ...