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

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2
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2answers
95 views

Cropping with GDALWarp in QGIS

I followed this post, the first answer, to clip a USGS Quad in order to remove the borders so that I can tile them. Basically it utilized the lat/long at the corners in a .txt file to import a ...
-1
votes
2answers
172 views

How can I project a power line net in QGIS?

I am working with power lines net using the software QGIS. I would like to know which plugins or tools do I need to be able drawing (projecting) them.
0
votes
3answers
90 views

How to set a coordinate transformation GRID

Does anyone know how to set a coordinate transformation in qgis so I can measure the distances in meters or kilometers? If anyone has a clue, would be just great. Thanks!
2
votes
1answer
652 views

Why do I get an error when I try and clip a shapefile to a shapefile using ogr2ogr?

I want to clip a shapefile to a shapefile. The input shapefile is a 1 m vector grid generated in QGIS. The tile I'm clipping to is just a simple polygon (the geometry is contained within the 1 m ...
0
votes
0answers
217 views

How to create .dem file in QGIS?

I have an elevation data in .asc file, but need to convert it to .dem file to later use in COMSOL. However, in Raster--> Analyzes-->DEM I got just error message: ERROR 1: DEM Default Setup: Importing ...
1
vote
1answer
233 views

Possible to run “Merge shapefiles to one” algorithm from Python script?

Developing a python script in QGIS 2.2, I can run algorithms from the Processing plugin fine such as those from QGIS geoalgorithms and SAGA. Can you do the same for the algorithm "Merge shapefiles to ...
1
vote
2answers
315 views

Qgis making a backgound map for topolines on Garmin

Hi I am a new user of QGIS, I would like to make a Background map with Topolines in gmap or img format. So I started off with Opendem shape files. I have sucessfully combined the tiles I want into one ...
1
vote
1answer
324 views

How to programmatically export a composition as image?

QGIS Print Composer has tool "Save As Image" and I found appropriate function in QGIS source code exportCompositionAsImage. Is it possible to get access to existing Print Composer from Python console ...
0
votes
2answers
3k views

how to generate a NDVI in QGIS [closed]

i have tried using raster calculator to generate NDVI and tried searching for but couldn't find it. is there any other way to extract NDVI and what are the procedures to generate NDVI in QGIS.
3
votes
5answers
592 views

How to place labels under a vector layer?

I want to place the labeling under a layer. In QGIS 2.2 apparently the label appears automatically at the top. Can someone help me. (see attachment) example:
3
votes
0answers
82 views

How to find the minimum number of inspection points?

I am working on a pipeline inspection project and there is a high liklihood that some inspection tool deployment/retrival station will need to be installed on the pipe network. the problem is ...
1
vote
2answers
281 views

Using the Rule-based style to calculate each grid cell from overlaps

I am using the Rule-based styling properties (QGIS 2.2) to determine the colour of grid cells for a merged shapefile. Each grid cell defined by its ID may be overlapped by several layers as defined by ...
1
vote
0answers
87 views

Command-line tool for writing a print-composer to file?

I'm looking for a command-line tool, to write a previously generated print-composer to an image-file. The following resources I already saw: Related questions (1, 2) A gist Nevertheless, all them ...
0
votes
2answers
723 views

Any clue how to read a .style (ArcGIS) file in Python, for converting into another platform-specific format? [duplicate]

The problem I am face with is that I have all my data as shapefiles but my organization works with only 1 ArcGIS license. Migrating to QGIS to prominent amount of work, I need to convert my ArcGIS ...
0
votes
0answers
66 views

Scale keeps changing in QGIS composer?

Every time I pan the map content in the QGIS composer window the scale changes. Is there a way to make it stick at specific scale?
2
votes
2answers
121 views

qgis raster style 'no data value' checkbox is ignored - what's a good workaround?

See bug report filed here: http://hub.qgis.org/issues/10236 Note the initial bug report got 'fixed' but that fix introduced this new error, so the issue was reopened a few days ago. Anyway, it ...
1
vote
1answer
50 views

How to remove ghost layer in Qgis?

I added a delimited text layer to a Qgis 2.0 project, working in Windows, but it got added wrong: It didn't appear in the list of layers on the left panel, nor did it show in the map canvas. However, ...
1
vote
0answers
162 views

How to keep all the unique columns of the shapefiles after merge?

Writing a script where the user is asked to select a directory which contains Folder_1 and Folder_2, both containing shapefiles and run various algorithms. The basic logical process of the script is: ...
1
vote
2answers
286 views

Retrieve Elevation from Color in Raster DEM

This might turn out to be a newbie question, and that would be because I'm fairly new to GIS work, but extensive online searching, asking associates with some basic GIS knowledge and hours in various ...
0
votes
1answer
497 views

Best Resampling Method for DEM reprojection in QGis

I need to reproject a DEM (aster file) in order to have the same CRS as all my other project data - I have different SHP for the same DEM's location but they have a different CRS. Which resampling ...
1
vote
2answers
78 views

Coordinate Reference System issues between SHP and Raster file

I am having an issue with the CRS of a given Aster DEM. I have downloaded a Aster DEM from www.oziexplorer3.com which comes with the EPSG:4326 - WGS 84 as the CRS. This is a DEM from Gabon, and all ...
3
votes
1answer
75 views

How do I select all outermost features

Is there anyway in QGIS that I can select all the outermost features on a map? On an island that would be all that have a coastline. edit: This is what I'm trying to select:
0
votes
0answers
24 views

How to build an optimization model? [duplicate]

I want to make a model using QGIS. Is it possible? Then how can I develop a model. can anyone help me?
0
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0answers
46 views

qgis: module crashed or killed

using Grass 6.4.3. via Qgis 2.2.0 Valmiera (standard installation package): Why would Grass modules suddenly produce a "module cashed or killed" error. specifically in relation to r.surf.idw2 and ...
2
votes
1answer
524 views

How to create atlas along line/route in QGIS

I'd like to create a mapbook along a given route that is designated by a single linear feature. Is it possible to have QGIS (2.2) automaptically compose a series of pdfs that over lap by a given ...
0
votes
0answers
44 views

QGIS - Obtain elevation profile [duplicate]

I wish to obtain a bathymetry profile along the selected path (Google Earth calls this feature "elevation profile". Can QGIS 2.2 provide this? I created a layer using the WMS service to load the ...
1
vote
1answer
100 views

QGIS - View bathymetry info in the status bar

PolyGo suggested that I split my earlier twofold question into separate questions. So: I am new to QGIS or any GIS software so please forgive me if the answer is obvious to you. I wish to view the ...
0
votes
1answer
127 views

Modifying Fields in QGIS

I'm pretty new to Quantum GIS, and I was looking to add zeros to a field I was having some trouble with. I learned through browsing a few posts here that existing fields can be modified by defining ...
0
votes
0answers
69 views

Enlarge region/features in shape file

I'm completely new to QGIS. I have a shape file over the counties in Denmark (see here for what the shape file looks like). The counties around Copenhagen are rather small and I'd like to add an ...
1
vote
1answer
83 views

Unable to install QGIS 2.2 successfully?

I'm having problem in installing QGIS 2.2. (64 Bit). After downloading & installing, when I click the OSGeo4WShell, I get a message: C:\***.exe not a valid win32 application and ends with: ...
0
votes
0answers
139 views

Save map canvas as image with drawings

Is there any way to save the map canvas as an image, with the drawings on map? I draw a line on map, and saved it as image, but only the map saved(without line). I used the following code.. ...
0
votes
0answers
18 views

Created polygon appears to move when zooming in (qgis)? [duplicate]

I am using QGIS 2.20 on a Windows 8.1 64-bit laptop. I have a shapefile that includes a polygon that I created from digitizing a Google Satellite image from OpenLayers Plugin. Here is my problem: ...
1
vote
3answers
171 views

How to measure areas using an official CRS which is not available in QGIS?

I am very new to QGIS and doing a project on Glacial Lake Outburst & Flooding (GLOF). I am trying to find the area of a lake using images from Google Earth 7.0.3.8542. I am using the WGS84 CRS ...
6
votes
1answer
3k views

Where is the Merge selected features button in QGIS 2.2?

Ever since I updated to QGIS 2.2 I've been a bit lost with the new menu layout (I was running on Wroclaw until then). I can't seem to find the "Merge selected features" button. I need to merge ...
2
votes
3answers
103 views

Can QGIS merge CSV files with different colums? [closed]

I am trying to merge a month's worth of daily CSV files without using ArcGIS. Each file has ~25,000 entries so this is a high data load project. Sample data can be found here. Note that we are using ...
1
vote
0answers
17 views

QGIS merge selected features tool malfunctions due to geometrical errors [duplicate]

The issue occurs using the 'Merge Selected Features' tool when there are geometrical errors in the features (not all are picked up by the 'check geometrical validity' tool). In 2.2 Valmeria, the ...
1
vote
0answers
32 views

Reclassify based in neighbour polygons

I would like to do a simple operation in QGIS and I am not sure about which is the best option. I have a polygon shapefile and each one has one class attached. I want to reclassify one of them based ...
0
votes
1answer
151 views

Problem when converting Shape file to KML files in QGIS

Problem when creating KML files in QGIS? I select Layer CRS as WGS 84 (EPSG:4326) When I open the kml layer in Google earth it is wrong. In Google earth, appears some segments every where on the ...
0
votes
0answers
44 views

Couldn't load PyQGIS in QGIS 2.2 on Ubuntu 14.04 [duplicate]

This issue appears to be occurring with some frequency to folks in some shape or form. I upgraded from ubuntu 12.04 to 14.04, with loss of python functionality. My QGIS version is 2.2 from the ...
0
votes
1answer
44 views

QGIS API documentation in French?

I am looking for a document which explains what the API of QGIS is, with examples of this API but in French.
2
votes
2answers
147 views

How to get the Measure Line in Yards (not Feet)

I'm using Qgis Dufour 2.0.1 and the Openlayers Plugin for images. I'm working on a golf course project where everyone thinks in yards. I've tried different CRS (now working the State Plane Missouri ...
1
vote
0answers
196 views

Problems installing libgdal-ecw package

I have problems to visualize ecw files for qgis 2.3.0 using ubuntu 12.04 LTS. From terminal, following the instructions for qgis 1.8 found at ECW for QGIS 1.8 in Ubuntu 12.04, because launching the ...
0
votes
0answers
95 views

QGIS Small multiples / animate across columns

I want to turn each column of a shapefile into choropleth. I have over 100 columns, so rather than manually classifying each column and exporting an image, I was wondering if there is a way to ...
4
votes
3answers
284 views

How to compute the outline of multiple tracks?

I have multiple gps tracks with depth data gathered from the lake. The tracks are overlapping/intersecting. I want to get an outline polygon. I have a multi-line shp. I've tried to diffuse it in qgis ...
1
vote
0answers
112 views

GeoTIFF Mosaic/Crop/Translate in QGIS?

I routinely have to mosaic multiple GeoTIFFs together, extract a rectangular area, and save that area as a JPG with a world file. Typically I've been using commercial software for that (Geographic ...
2
votes
1answer
54 views

Resolve polygon parent relationship in QGIS

I have a layer in which, following geometry processing, the polygon of a zone that is a full enclave to another seems to have become its child object, which I think will cause problems down the line. ...
1
vote
2answers
198 views

Any difference between EPSG:3003 and EPSG:102091?

I am working on QGIS 2.2.0. The PRS I am working on is Monte Mario / Italy zone 1 (EPSG:3003), with the following parameters: PROJCS["Monte Mario / Italy zone 1", GEOGCS["Monte Mario", ...
1
vote
1answer
372 views

How to get QGIS layers style in a single file

I have layers on my QGIS project. Rivers Water pipes Gas pipes ..... I set the color, width, size of these layers. All layers are different style. I want to use these styles in geoserver. I have ...
0
votes
2answers
96 views

Is there a way to run spatial join within tolerance?

I have some data that should be spatially joined, but from small precision differences (less than 1 in) they aren't joined. I've found no way to add tolerance to qgis spatial join operation. Is there ...
0
votes
0answers
142 views

Is it possible to get WMS feature info for the WMS layer in the QGIS web client?

When I load a wms layer in qgis, it's possible to get feature information. When I open the web-gis-client on my server, it's possible to get feature information for all layers but not the wms layer. ...