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

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3
votes
1answer
87 views

Add a single column to multiple SHP

I was looking for a way to add a new column to several shp (simple polygons) at the same time. I don't know much about batch command. This new attribute is also a little bit tricky : I need to ...
2
votes
1answer
353 views

How to get shapefile extent from standalone script?

I am trying to obtain the extent of a polygon in a shapefile. I am running a standalone script which will create a grid based on the extent of the polygon. I have tried 2 methods: one from the ...
1
vote
1answer
216 views

QGIS virtual raster - insufficient permissions

I'm trying to create a virtual raster in QGIS 2.6.1 64b on Windows, but I get the message: "The process failed to start. Either the invoked program is missing, or you may have insufficient ...
2
votes
2answers
110 views

Building a python plugin on qgiq 2.6.0 [closed]

Plz I need help, Im about creating a python plugin for my project , I already compiled it but Im now facing a real problem while the installation , it seems to me that there is issue about the ...
3
votes
1answer
827 views

How to add a column/feature with PyQGIS 2.x?

I'm using PyQgis 2.2 and I'm creating a plugin. I want to add one feature/column to a shapefile. But I get error.. I've tried to do this as it's shown in Cookbook: if caps & ...
3
votes
1answer
473 views

How to copy paste layers from one QGIS project to another?

Using QGIS 2.4, how can I copy one or more layers (with its properties, style, and the path of the source data) on QGIS and paste it in a different .QGS project? I tried to make this, clicking in a ...
4
votes
1answer
1k views

Removing a vector layer from QGIS [duplicate]

Considering my program is generating a shapefile that has to be added to the "Layers" tab in QGIS interface. However, once the utility of the layer is completed, I need to remove the layer in the ...
1
vote
1answer
71 views

Keep selection order when Copy & Paste From Attribute Table in Qgis

When copying some selected points listed in the Attribute Table from QGis to Excel the order seems to get lost. Is there a way to keep the selected points in the order they were originally selected?
5
votes
1answer
1k views

NDVI from ESA's Sentinel-2 training data

I'am trying to generate an NDVI map using ESA's Sentinel-2 training images, which can be found at https://spot-take5.org. I tried using QGIS's raster calculator to create the NDVI image, however quite ...
1
vote
2answers
128 views

QGIS2.6 postgis relation between tables

I have three tables in Postgis: points called location(gid (pkey),name) example (1,Paris) temperatures named Temp(idTemp(pkey),TempValue,date) example (1,12,2015-01-01) relation between the two: ...
1
vote
1answer
632 views

Qgis Text/Annotation as layer

Is there a way to add text/annotation to my map in QGIS as a layer? I have a map of vegetation types an point data the text (field names/flurnamne) should be between these two layers. It there must ...
1
vote
0answers
132 views

Problems using the SAGA in processing framework with qgis 2.6.1 (ubuntu) [closed]

I've got problems using saga in the processing framework within qgis 2.6.1 and SAGA 2.1.4 To solve this problem I was obliged to correct the line 352 of the python file '/usr/share/qgis/python/...
3
votes
0answers
180 views

How to calculate areas in raster files

I got three files. The first is a shape file for country boundaries and the second and third are two raster files with the global land covers for 2005 and 2009. I'm thus encharged to calculate the ...
5
votes
1answer
338 views

How to create accurate heat maps and hot spot maps in QGIS? [closed]

I am mapping 5 heritage sites using DGPS point data. Each site has 100s, and in two cases 1000s, of points representing various attributes. I want to show the density of attributes and then ...
2
votes
0answers
272 views

Using QGIS legendInterface from standalone

In Python console from within QGIS, we use qgis.utils.iface.legendInterface().moveLayer( layer1, 1 ) to make modifications to the legend. What is the equivalent in a standalone python script ?In ...
4
votes
1answer
2k views

How to remove layer names from the print composer legend?

I'm creating a map in QGIS Composer that is the result of two merged layers. The legend (screenshot below) is adding two rows with the titles of the layers. The edit property sheet does not give me an ...
1
vote
1answer
260 views

How to change the raster format using QGIS translate?

I tried to change a raster format from .tiff to .asc using Qgis's 'translate'. As a result, I get 3 files: a PRJ, XML and a file without extension just a plain file... What could it be happening? I ...
5
votes
2answers
261 views

Is it possible to save qgs file as older version?

I just got installed the version 2.6 of QGIS (OSGeo4W) on Windows 7. I am exploring the new capabilities and the compatibility of our tools with this new version, however, i have to keep on working on ...
1
vote
0answers
37 views

QGIS Points are not retaining original attributes

I am trying to map birth and death locations for several hundred people in the US and Europe (for a total of 532 points in one layer). Twice now I have discovered that somewhere during this process (...
1
vote
1answer
55 views

oracle VectorLayer without geometry - How to get attributes?

I have a prolem to iterating over a oracle VectorLayer without geometry in QGIS 2.6. self.uri = QgsDataSourceURI() self.uri.setConnection("localhost", "port", "xe", "name", "password") self.uri....
0
votes
1answer
2k views

Why do pdf/image exports fail with OpenLayers Bing layers? [duplicate]

When I try to export a print composition it generates a 0kb file. Is not possible to open this file. It happened the same with export as image option. The print composition model is coming from a ....
3
votes
2answers
546 views

IdentifyFeature() use via PyQGIS?

Intent is to have two variables (QgsVectorLayer and feature.id() within said layer) as input for the Identify feature map tool in Qgis (2.6). Wondering if a feature can be selected programmatically (...
1
vote
0answers
68 views

how to use a database's table data in QGIS [closed]

I have already loaded a MySQL database as a layer, one of the tables contains data that are coordinates of some places, how to plot these data on a map(for example google maps)?
2
votes
1answer
133 views

How to deal with data-defined SVG paths in a project used on Windows and Linux?

I have a project QGIS used in both Linux and Windows, synchronizing the working directory with dropbox. The project uses relative paths, so that the directory structure is observed only from the ...
2
votes
0answers
131 views

How to display row and column of a selected pixel in QGIS?

In QGIS, I can use the identify tool to get the pixel value and the coordinate for a selected pixel, I also have a coordinate capture tool to display the selected pixel in another coordinate system. ...
0
votes
1answer
134 views

Export KML from GeoJSON in QGIS and coordinates change?

I'm very new in this area. I have a geojson vector layer file, with coordinates like { "type": "Feature", "geometry": { "type": "Point", "coordinates": [ 487677.2993499999866, 112018.26101 ] } }, ...
1
vote
0answers
191 views

How to include 3D break lines in QGIS raster interpolation

I wish to add a break line to an interpolation of a set of survey points to simulate an elevated ridge in the survey area. Using QGIS 2.6 on Windows 7. I have created a polyline shapefile with a ...
2
votes
0answers
280 views

Import vtk file in grass gis

last summer I made the relief of a cave, and at this time I returned with Therion software. This survey is in 3d and I can save it in the formats .Lox, .3d, vtk. I would like to import it in grass or ...
4
votes
3answers
2k views

How to efficiently access the features returned by QgsSpatialIndex?

The PyQGIS Cookbook explains how to set up the spatial index but it only explains half of its usage: create spatial index — the following code creates an empty index index = QgsSpatialIndex() ...
3
votes
2answers
266 views

How to add today's date into an attribute table using QGIS Processing modeler?

I am looking for a way to use the Processing modeler to add a date field to an output dataset in QGIS 2.6.1 I have tried using the field calculator algorithm without success. (Also the advanced ...
1
vote
0answers
37 views

How to match UTM squares between Excel and Shapefile?

I have an excel file with locations displayed in UTM 10kmx10km squares. I also have a shapefile with those same UTM squares and their coordinates, however I cannot seem to figure how to project the ...
0
votes
0answers
75 views

QGIS Crash: Enter Credentials

just wondering if anyone has come up against this issue...in the office QGIS will come up with an 'Enter Credentials' box with 'Error: Too many clients already'. When you enter your username and ...
1
vote
0answers
28 views

QGIS street labelling when rotating in composer

When labeling streets in a QGISmap everything's OK, no label are upside-down. But I need to rotate at 180° in the composer. Labels of lines don't flip, so they are upside-down! I tried to "show ...
1
vote
0answers
55 views

QGIS join by location not returning for features

I have eight contours/features in one shapefile (contour.shp) that i want to find the number of population within each contour, this is in another shp. I am using join attributes by location to do ...
1
vote
1answer
274 views

How to add fields to shapefile from standalone script?

When I run the following script via OSGEO4W64 Shell, I receive the following error when trying to run the qgis:fieldcalculator algorithm: 'NoneType' object has no attribute 'mapCanvas' I read ...
1
vote
1answer
59 views

Efficiently working with converting vrt rasters to greyscale in QGIS?

I have large raster tile sets working well in QGIS (Ordnance Survey UK data). Sometimes I want to grey/fade these to make my data clearer to see. Attempting to access properties on QGIS for the VRT ...
1
vote
1answer
113 views

Advice on Map Maker Pro versus QGIS [closed]

I am an ecologist in the process of trying to decide whether to purchase Map Maker Pro or utilize the free open-source QGIS platform. Most of our needs are associated with basic map making. I am a ...
0
votes
2answers
87 views

Why won't my csv file imported as a vector layer have attribute table headers?

I have a .csv file that has unique identifiers that I'd like to join with some legislative district shapefiles in QGIS. I've done this before, and the joins all worked fine -- and technically it still ...
0
votes
0answers
42 views

Files generated with QGIS are invisibles for my system (windows 8.1) How can I Solve this?

My use of QGIS is basic but very important in my job. My final product usually is a Cartographic map (PNG or BMP image). Since the last updated (QGIS 2.6.1 Brighton) I have problems with every file ...
1
vote
1answer
40 views

Eliminating pixels of a Merged image

I need to change the value of pixels that where created in an image as a result of merging 2 rasters, this new pixels have a value of 0. The problem is, that there are pixels with 0 in the original ...
2
votes
1answer
590 views

QGIS Linear Referencing

I'm not sure how to ask this. Essentially; I work for a survey company doing gas lines GIS. We use QGIS. We create hand drawn sketches of pipelines containing all sorts of information including: ...
2
votes
1answer
527 views

How to Set SRID in Spatialite

How do you update the SRID in a SpatiaLite table? I am using the QspatiaLite plugin or the SpatiaLite_Gui program to send this SQL to the table: UPDATE myTable SET geom = SETSRID(geom,26910) ...but ...
1
vote
1answer
104 views

What's the correct syntax for Execute SQL in Processing QGIS 2.6?

I made a small model with Processing in QGIS 2.6. The final layer should be the result of a SQL query. Now, in the Execute SQL dialog window I can add the query: select name, max(ele) as ele, geom ...
6
votes
1answer
152 views

Create buffer based on polyline without line end caps and without dissolving the created polygons in QGis

I have a projected line layer (Shapefile) in QGIS. For every line segment I want to create a polygon without line end caps. The resulting polygone should not be dissolved to a single one. I tried ...
1
vote
0answers
51 views

QGIS 2.4 Join Attributes Table tool does not recognize non spatial data to execute

I'm using the graphical modeler in QGIS 2.4 to automate some processes and certain tools are basicly necessaries to get to the point. The "Join attibrutes table" tool, despite it's basic, can help us ...
1
vote
3answers
661 views

Can't use Raster Calculator with two different rasters

So, I have several maps like this one: And with the proximity tool and a coastline shapefile I made this output, representing the distance to shoreline: Now, I want to combine both using the ...
1
vote
1answer
2k views

Convert polygon to point with QGIS [duplicate]

I work with QGIS and I tried to convert polygon into point. I need points all over the perimeter of the polygon. I saw several answers like: Problems converting polygon to point but I didn't see an ...
3
votes
3answers
299 views

Which tool/reference for address geocoding?

I have to geocode several corporate sites (a big excel file), close to Paris (France). I would like to geocode this file based on the addresses. Could you tell me the best tool for this task (...
1
vote
0answers
45 views

Error after executing hex grid script in QGIS 2.6 for Mac

I hope some of you might help me in solving this problem: I'm trying to load a script with QGIS, hex grid from layers bound, with a population shape file (popp.shp in egis sample data folder). After ...
1
vote
1answer
140 views

Connect OpenLayers3 Client with QGIS Server

at the moment I am developing a map editor on a web. After researching at the internet about map clients, I decided to use OpenLayers3 client because it is very simple an has all the tools i need ...