Tagged Questions

Version 2.0 of QGIS, is a user friendly Open Source Geographic Information System (GIS) desktop application licensed under the GNU General Public License.

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1
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1answer
31 views

Use PyQGIS to import CSV and draw points using different color

A CSV file contains columns latitude, longitude and color. uri = "file:///C:/data/balls.csv?type=csv&xField=longitude&yField=latitude&spatialIndex=no&subsetIndex=no&watchFile=no" ...
3
votes
1answer
111 views

How to create a cluster of crashes?

I have a shapefile with 52K points of road accidents, between 2007 and 2012. Each accident has a severity index. I want show clusters of 5 accidents (at least), for each year, that have a severity ...
3
votes
1answer
49 views

Spatialite WITH clause issue

I've encountered an issue: when I try to execute in Spatialite_GUI query that contains WITH clause I get SQL error: near "with": syntax error. Also WITH unlike SELECT and other keywords is not ...
3
votes
1answer
39 views

Superimpose OTB application via Sextante cannot load parameter

I am trying to perform a pansharpening using OTB via sextante. According to the cookbook I first need to superimpose the Pan and XPS images: http://www.orfeo-toolbox.org/CookBook/CookBooksu36.html ...
9
votes
1answer
211 views

Can PostGIS and QGIS provide dependable multi-user editing?

After considering a few options, I'm trying to give my 15-20 QGIS 2.2 users the ability to concurrently view/edit one or two basic point PostGIS layers, largest one has just 16,000 records. I've ...
1
vote
0answers
13 views

Importing QGIS file in Eclipse for Android application?

Using ECLIPSE for android development, and also QGIS for customizing maps, I want to know if I can import the data in QGIS into my android application so that the data of my android applcation will be ...
1
vote
0answers
20 views

QGIS crash on logon screen : Python

When I run QGIS, it loads plugin and everything until starting python appears. I have python 3 installed. I need Python 3 and can't remove it from Python path. How do I use QGIS? Isn't QGIS bundled ...
4
votes
1answer
71 views

How do I plot points that have relative coordinates rather than total station coordinates on a map?

I have about +100 points of various descriptions from an archaeological survey. They are the backlog from years of excavations BEFORE systematically using Total Station at the site. For each artifact ...
2
votes
1answer
36 views

How do I programmatically automate “Random Points” in QGIS?

The random point tool in QGIS 2.4 works perfectly fine through the GUI, but I can't figure out how to automate this tool via Python and/or the modeller. Specifically, under the menu items: Vector | ...
1
vote
1answer
39 views

QGIS attributes pop-up window is empty

I have a problem with QGIS (2.2 and 2.4). Sometimes, when I'm going to insert some new features on a layer, the pop-up window that appears at the end is empty (all gray, no attributes are displayed). ...
0
votes
0answers
26 views

Editing attributes in a custom feature dialog box

Is there any special trick to getting a custom dialog into an editable state (setEditForm) I see there is an editable() method, but no corresponding setEditable(). Setting the layer as editable ...
2
votes
0answers
30 views

QGIS - is it possible to select the columns shown with “Identify features”?

In QGIS, I have created a join to an attribute table with some 60 entries. I am only interested in seeing 3 of the columns, specifically address data. I can see no way of excluding the unwanted ...
0
votes
2answers
85 views

Georeferencing window won't open QGIS 2.4

I had the georeferencer window open in QGIS 2.4 while project was running, I accidentally closed the Qgs document with the georeferencing window open (worked absolutely fine till then). When I opened ...
1
vote
1answer
29 views

Red x marks along lines after adding a length field?

I added a "length" field to a shapefile of lines called "roads". QGIS puts red x's along the length of the road afterward. Why is this, and can I make these go away?
1
vote
0answers
54 views

Formatting Google Places API GeoJSON and Import to QGIS?

Hi Stackexchange I'm trying to export JSON or XML data to my desktop and import it to QGIS. This is the URL I'm using but it appears to be incorrectly formatted: ...
0
votes
1answer
39 views

QGIS Python console - save image from bounding box

I want to save an image from QGIS but the save image functionality feels limited. My question is if it's possible to use the python command line to save an image at a specific zoomed in scale and to ...
4
votes
1answer
62 views

Adding super/sub script in QGIS text annotation?

How can I add a super/sub script in a QGIS text annotation? For example, 44.95 mi^2.
1
vote
1answer
102 views

Why is feature.geometry() None in my user-defined expression function?

I'm trying the user-defined expression functions for QGIS, as listed on Nathans blog: http://nathanw.net/2012/11/10/user-defined-expression-functions-for-qgis/ I always get the feature.geometry() as ...
1
vote
0answers
20 views

Labels on the QGIS WMS layers are not drawn according to the style definition

I have an issue regarding the styling of labels of WMS layers using QGIS server. I can't seem to get them to display how I want. What I did: create a QGIS project (2.2 on Mac) with a layer from a ...
2
votes
1answer
54 views

Filtering MSSQL layers in QGIS doesnt work

In my QGIS Plugin I am filtering layers with this Python code: FeatureIterator = layer.getFeatures( QgsFeatureRequest().setFilterExpression ("Fieldname='SomeValue'") ) for feature in FeatureIterator ...
1
vote
0answers
36 views

Is it possible in QGIS print composer to include a numeric scale in an html box?

For work I always have to create a table with my name, project name, date etc. into my map layouts. I also need to include the scale like "1:150000" in that table. So far I am solving that by ...
1
vote
1answer
33 views

Deleting vector lines beyond image extents using QGIS?

I am using QGIS 2.2 I have one vector line layer (roads) that stretches beyond my base image (see below). I wish to have the roads "clipped/trimmed or deleted" right at the edge of the image's ...
3
votes
0answers
65 views

How to export data from sql server into shapefile in the decimal format in QGIS 2.4?

The last couple of days, I have been working on exporting data from SQL to a shapefile in QGIS 2.4. While converting into a shapefile, the data type changes automatically from Float to Integer in the ...
2
votes
1answer
63 views

Creating a graduated buffer in QGIS

I'm attempting to map cell phone towers and their range in QGIS. I'm wondering if it's possible to create buffers which change color intensity according to their distance from a central point. The ...
0
votes
0answers
12 views

Pyqgis 2.2 : get signal on feature added : error message

For my pyqgis plugin 2.2, I try to: def logFeatureAdded(self,layerId,addfeatures): message = str(layerId) + " has features added: " for feature in addedFeatures: message += str( ...
1
vote
2answers
84 views

Pyqgis 2.2 : zoom to layer extent?

Regarding my plugin pyqgis 2.2, i can load a vector layer succesfully. But when i try to zoom to the layer extent it does not work. How to do in order to zoom to the layer extent? Thank you very ...
0
votes
0answers
40 views

Get signal on edited feature?

Regarding my pyqgis plugin 2.2 , I've implemented signal on a vector layer event successfully. For instance, whenever i create a new feature, i can read a new basic message appeared via QGIS logging ...
4
votes
2answers
308 views

Best Landsat-5 TM band combination for detecting fire scars

I am looking for the best band combination with Landsat 5 imagery to detect fire scars.
3
votes
1answer
92 views

Qgis - Labels automatically resize to fit within the polygon

The question of my problem is simple, I want to make labels automatically reduce to fit within the polignos. Type the biggest size is 12 and goat decrease the size to be restricted to the limits of ...
1
vote
2answers
62 views

How to export a high-res world map image?

I'm trying to get some (very) large world map images (think 10k x 10k pixels etc), but can't seem to do it with QGIS, and would appreciate any help. Manually adding smaller images to a larger one ...
0
votes
1answer
42 views

Update OSM data already imported in qGIS

qGIS makes it really straightforward to import data from Open Street Map (there's a good tutorial here). However, despite this process is relatively straightforward, it takes some time to download the ...
1
vote
1answer
144 views

QGIS 2.4 (and 2.0.1): How to uninstall/reinstall a plugin where uninstall is disabled?

Plugin Raster->TerrainAnalysis->slope which had initially worked, started showing what another questioner referred to as a "crazy histogram": qgis2 slope analysis from NED data gives crazy histogram ...
0
votes
0answers
37 views

View tiled shapefiles in QGIS 2.0 or greater as one layer?

I have tiled vector data in shapefile format. I need to view them in QGIs 2.0 or greater. I was not able to find any usable solution (merging is not the way). I have tile indexes, which I use for ...
0
votes
1answer
76 views

QGIS to solve projection mystery in Postgresql

I downloaded some data from local agency. Per QGIS 2.2, I defined the projection to 'EPSG:3587 - NAD83(NSRS2007) / Michigan Central' in postgresql (maybe ArcMap). Data is in Postgresql 9.3. I am ...
1
vote
0answers
114 views

Invalid geometry

I'm working on some shapefiles in both ArcGIS 10.2 and QGIS 2.0. I have 3 files which I have cleaned of self intersections in ArcGIS using Repair Geometry. I have also checked for Overlaps using the ...
1
vote
1answer
66 views

How to interact with other layers in a QGis Python init function?

I am using QGis and making a Python script that sets the Python Init function to a custom UI file. I have a function with the following signature: def formOpen(dialog, layer, feature): ... I ...
0
votes
1answer
92 views

QGIS saving shape file wrong utf8 encoding in DBF?

I'm using QGIS for some SHP processing. When i save the file, the DBF utf-8 text encoding is wrong: Source DBF à0è0ì0ò0ù0 HEX: C3A0 30 C3A8 30 C3AC 30 C3B2 30 C3B9 30 Saved DBF à0è0ì0ò0ù ...
3
votes
1answer
99 views

Is it possible to rotate the *canvas* in QGIS

Can the canvas be rotated so north is pointing in some other direction than defined by the projection? This question answers with respect to the composer, but not the canvas. There is a related 5 year ...
2
votes
0answers
72 views

How can I label the pie charts in QGIS so the labels are written under the diagrams?

How can I label the pie charts in QGIS so the labels are written under the diagrams? My pie-charts are representing localities: such as villages, towns, cities. So, I want that their names appear ...
3
votes
5answers
165 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:
1
vote
3answers
99 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 ...
0
votes
0answers
27 views

take record from ms-access using python and show it in Qt

I have a ms-access database and i try to make QGIS plugin that take record from table and show it in Qt, database have format like this : NO Skala 1 Skala2 Rekomendasi ...
0
votes
0answers
27 views

Ground Sampling Distance

I am quite new to QGIS. I got an Orthophoto under QGIS. I want to calculate Ground Sampling Distance values of this image. Does anyone know how to do this under QGIS? I am using QGIS 2.2.0. I even ...
0
votes
1answer
24 views

Installing QGIS from non-packed file

I've been asked a question regarding installation of QGIS from an unpacked file on Windows, as the organization that wants to install it needs to run a thorough malware scan. Currently, the ...
0
votes
1answer
84 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
0answers
58 views

QGIS-Merge or create virtual raster files without losing definition?

I am new to QGIS and relatively new to GIS (so please be aware I am not that familiar with a lot of technical terminology). I am trying to merge several tiff files as either a virtual raster or a ...
0
votes
0answers
31 views

QGIS translate BAG surface to XYZ

I have a BAG (Bathymetry Attributed Grid) from NOAA which I wish to export to XYZ. The grid imports fine as a raster and plays nicely with most of the raster tools that I have tried. It does, ...
1
vote
1answer
52 views

Create a point C from point A in the direction of point B

I am very new to QGIS and GIS in general. I hope someone could help me figure this out. I have pairs of coordinates which signify the start and end of a transect line. I am trying to adjust the end ...
0
votes
1answer
78 views

Error with existing OSM QGIS style

I'm trying to use existing OSM style file like those of AsgerPetersen (https://github.com/3liz/osm-in-qgis/tree/master/styles/openstreetmap/geofabrik) or anitagraser's ...
0
votes
1answer
55 views

How to split a line at a vertex in QGIS 2.2? [duplicate]

Is there a plugin out there that will split a polyline at vertexes? My arcgis license isn't high enough to run the tool. I'm using 2.2.