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

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5
votes
1answer
1k views

QGIS won't install on Mac OSX, during install says “The Installation Failed.”

I have installed the requirements: GDAL Complete 1.11 framework package Matplotlib Python module and I've made sure these requirements are properly installed by checking library/frameworks and /...
2
votes
0answers
105 views

Unicode Decode Error while geocoding MMqgis

Running Qgis, trying to geocode a CSV file using MMQGIS Qgis gets to the 66th element (there are 119) and returns the error: Traceback (most recent call last): File "C:/Users/BPolinsky.MDC/.qgis2/...
1
vote
1answer
22 views

Is possible to add a web map service like streetdirectory to ArcMap/QGIS?

I would like to know if there is some chance to get web map like streedirectory.sg to arcmap or qgis. I need to use this map as a basemap that's why i'm looking for a way how to get this map to ArcMap....
1
vote
3answers
58 views

Cut part of raster with another raster (mask)

I have a raster which I want to cut. A second raster smaller, should be exactly the part where I want to cut the first layer (so I cut the same size as raster 2). The idea is that raster 2 become the ...
1
vote
2answers
65 views

Comparing string in one column to some others using QGIS?

I'm trying to write an expression which will return a TRUE or 1 type result if the string in "column3" is the same as the string in either "column2" or "column1". I've tried "column3" IN ("column2","...
1
vote
1answer
81 views

qgis-processing: how to specify optional outputs?

Suppose a script has a variable number of outputs, which may or may not be produced depending on settings: ##Input_layer=vector ##Output_1=output vector ##Produce_output_2=boolean ##Output_2=output ...
2
votes
1answer
40 views

How to solve the error: query must return columns 'id', 'source', 'target' and 'cost' in postgres 9.3

SELECT seq, id1 AS source, id2 AS target, cost FROM pgr_kdijkstraCost( 'SELECT gid, source, target, cost FROM road_network', 26, array[1055,2013], false, false ); I am getting the ...
1
vote
1answer
59 views

georeferenced JPEG images not intalling in QGIS correctly

I am trying do add georeferenced aerial images (jpg files) to my QGIS. They do not install properly. I either get a grey rectangle or bands of colour (mostly blue) that appear where the image should ...
1
vote
0answers
333 views

show some data on a map by OpenStreetMap from C# VS2013 [closed]

I am very new to Open Street Map. I have some data that need to be shown on a map by Open Street Map from C# VS2013. It can be WPF or windows forms. The data is about some statistics results by ...
2
votes
1answer
128 views

QGIS suddenly very slow generating atlas on PC?

I have been using happily QGIS for about 6 months, in the last week it has suddenly got much slower when generating an atlas using print composer. I am running QGIS 2.10.1 on a PC laptop (Windows 7, ...
3
votes
2answers
102 views

How can I display points with points displacement renderer without circleoutline

I understand the point displacement, but I would like to display the circle without the circleoutline. Even when I change the "circle pen width" to 0,00 it displays a fine line. And there is no ...
2
votes
1answer
409 views

How to run GDAL vector (OGR) tools from inside QGIS?

I want fingertip access to the GDAL/OGR tools, particularly ogrinfo, from the main QGIS screen. I currently run ogrinfo.exe in a DOS shell but this seems clumsy. Installing the GDAL Tools plugin ...
1
vote
0answers
38 views

Converting 3d images in meters to feet when exported to dxf

In QGIS 2.10, I am using the raster calculator to convert a metric elevated raster to feet and then create 2 foot contours (no problem). But when I dxf it out and put it in CAD, I can get the contours ...
2
votes
0answers
113 views

Are there any plugins that have functions like ArcScan in QGIS?

I am looking for a plugin which does raster scanning, like ArcScan. Typical QGIS Vectorization returns very bad outputs that have thousands of 'islands'. Also, can anyone please guide me on how to ...
1
vote
1answer
185 views

Edit GeoJSON attribute table

Is it possible to adjust tabel headers of GeoJSON files in ArcGIS? If yes, which max length has a row header? In QGIS there is no possibility to edit a GeoJSON table.
7
votes
2answers
639 views

How to download MOD16 (Modis Evapotranspiration) image?

I use a 'R' script for downloading MODIS imageries. However, it doesn't give MOD16 product. I could neither find the MOD16 product in earthexplorer website. Though the desired product is available at ...
3
votes
1answer
198 views

Qgis: Export only some columns of the selected objects to CSV

I have a layer with a table containing several columns. If I right click on the layer --> Save as.. --> CSV and chose to only include my selection I get a nice CSV file with all columns for the ...
2
votes
0answers
59 views

Creating new PostGIS connection in QGIS?

I am trying to create a new PostGIS connection and I am doing as it follows: The password I inserted is postgres, I don't know what should be inserted there. And when testing the connection, I get ...
2
votes
0answers
49 views

identify and calculate area of valleys

I have a shape file (points) that contains the coordinates of a number of cities in a mountainous area (valleys separated by mountain ridges), and a DEM of the area. I would like to calculate the ...
1
vote
0answers
52 views

regroup the close points [closed]

I have a list of 10 000 points, and I wish consolidate 15 points each in a block in the vicinity. I use arcgis, or mapinfo qgis, I just need the method.
2
votes
0answers
34 views

v.clean batch process withing QGIS 2.10 (PISA)

I get an error message when i try to creat a batch for v.clean operation.. Algorithm v.clean - Toolset for cleaning topology of vector map. starting... local variable 'filename' referenced before ...
1
vote
0answers
37 views

More control on raster colour maps? [closed]

I'm playing with various raster layers (DEM, geophysical data such as gravity or gamma-ray, etc). QGIS does a fine job at reading and displaying them, but I'm looking for more control on symbology, ...
0
votes
1answer
59 views

Rotating map canvas for QGIS 2.8.3 atlas generator?

I have a atlas coverage layer that follows a water network for use with the QGIS atlas generator. I am having issues getting the map canvas rotation to update dynamically with each coverage feature. ...
3
votes
1answer
137 views

Is there are way to import non-geo JSON files into QGIS?

Here is a json file containing various attributes relating to countries. However, it does not contain any geographic data. http://bost.ocks.org/mike/nations/nations.json I would like to join these ...
2
votes
1answer
125 views

Fully symbolize a vector field marker in PyQGIS

I'm designing a symbol for an external application that needs to be a vector field marker combined with a simple point marker, displaying a line at a certain angle around the center point. In PyQGIS, ...
3
votes
1answer
421 views

How to find out coordinate system to use pre-1940 Soviet map as raster

I am trying to use this map as a raster but I am not having any success in QGIS. I tried in Georeferencer to open raster and used these settings: Transformation: Thin plate spine Resampling Method: ...
3
votes
1answer
196 views

QGIS Topology Checker Wrong

I use topology checker and add a rule that polylines must not have dangles. It find errors for all 36 polylines but I think some topologies are correct at the right side. Can you help me how can I fix ...
1
vote
1answer
225 views

Adding label to QGIS map composer through Python script?

I need help in adding a label to QGIS map composer through python script. I could add a label but it is incomplete. The label is like this: 27-02-15 11-25. It only shows the first part: 27-02-15. I ...
2
votes
1answer
204 views

How to connect input parameter to the field calculator algorithm within the graphical modeler?

I am building a model in the graphical modeler of QGIS 2.8.1 Wien and I would like to give the option to the user to enter a number in the model with which a selected field will be multiplied, but I ...
0
votes
3answers
415 views

Running TauDEM in QGIS?

How do you configure TauDEM 5.1.2 to run in QGIS 2.10.1? TauDEM plugin activated, and visible in the Processing Toolbox (Advanced Interface). However, TauDEM tools do not run. I get the message '"...
0
votes
0answers
241 views

Histogram matching of two NDVI images

I have two Landsat 5 NDVI images (Surface Reflectance products) from the same period of the year (only a few days apart), but one is from the 1980s and one from the 2000s. I am trying to do a change ...
6
votes
2answers
227 views

Create large amount of random points in binary raster

I want to create a point vector dataset of 10000 points (or larger) within a binary raster, where the points should be constrained to areas where the raster value is 1. I tried the following steps. ...
1
vote
0answers
17 views

QGIS change zones in a raster to grayscale by polygon overlay

I've got a raster ortophoto and a polygon layer: I need to alter the raster layer as follows: Everything that is inside the polygon (overlaying) should stay as it is right now (in color). The ...
1
vote
1answer
81 views

migrating geotiffs to iGIS tiles

I recently shifted maps and waypoints from Delorme Xmap to QGIS on my Mac and wish to use iPhone/iGIS as the GPS (together with the Garmin GLO receiver). Everything is good in QGIS, but I need USGS ...
3
votes
1answer
119 views

Clipping points by a polygon attribute in QGIS

I am trying to clip a point layer with a polygon layer. My polygon layer has multiple polygons (e.g. country with different states). I am wanting to clip the point layer based on the different states ...
2
votes
1answer
32 views

Using Join, Merge, Dissolve in QGIS?

I am new to QGIS. I have two layers: Layer A: Large polygons joining areas, lets call them countries. Layer B: Smaller polygons(States) containing population count data within the large areas(...
4
votes
1answer
69 views

Adding a PyQGIS Plugin to the Database Menu

I am developing a plugin which I would like to add to the Database menu instead of the default Plugins menu. According to the PyQGIS Developer Cookbook all I have to do is add category=Database to ...
1
vote
0answers
50 views

QGIS choropleth map

In QGIS, when I change from single symbol to a graduated style, the map "disappears." When I change it back to single symbol, the map "reappears." The issue doesn't appear to be the scale, since it ...
3
votes
1answer
67 views

QGIS label calculation always renders zero

QGIS 2.8.3/Windows. I'm trying to use the area of a paddock as its label. The layer is a shape file containing a single polygon. In Layer Properties/Labels/Label this layer with I define an expression:...
2
votes
1answer
63 views

Graticule padding in QGIS map copmposer

I am trying to print a map like the image below. And I have a problem with grid and graticule. I understand that the best way to have a grid (in UTM, meters) and a graticule (in GMS) is by adding both ...
1
vote
1answer
34 views

error when merging geotiffs

I have a problem with a actually simple task: I want to merge 12 Geotiffs in QGIS. With Raster => Miscellaneous => Merge there is always an error saying: xyz.tif does not exist in the file system, ...
1
vote
2answers
42 views

Changing Computer, Update file roots. QGIS

I am due to finish work with my current employer, and leave all my QGIS work behind. I have about 100 different project files set up, each for a different client. Some pull from a common GIS database,...
1
vote
2answers
69 views

Getting number of objects in attribute table using PyQGIS?

I have a layer and I would like to access the number of rows the attribute table has from my code. Is there a way to do that without doing it like this: Index = 0 for Feat in Layer.getFeatures(): ...
1
vote
0answers
53 views

QGIS Copy Attribute Table To Excel - where does the new lines come from?

I have an attribute table with 3100 lines. I selected the whole table and pressed the button 'copy selected rows to clipboard', afterwards I pasted them into an excel-table. Now I have 27 lines ...
2
votes
1answer
524 views

How do I show only the selected features from an attribute table on a layer?

One of the layers has around 5000 attribute entries, based on a CSV file of species records. All the features are of course shown on the map layer. How can I select a specific class of features so ...
1
vote
0answers
29 views

Qgis -> DXF2ShapeConverter -> Inscriptions in Qgis

Sorry, but this is my first question which very often was asked . It has not yet answered very well. I would like to import a DXF with captions in QGIS. I have already tried this with the DXF ...
3
votes
1answer
64 views

Create default QGIS actions / define my own default actions

I have created a simple action that should be used to several users. Then, I'd like to put my action among their default action list. Put it simply, how can I create a default qgis action in a given ...
2
votes
1answer
34 views

Is there a way to apply the “Select features by rectangle\polygon…” function on multiple layers simultaneously?

I have put a map together using openstreemap data that is intended to be used as a base for different projects. However due to the amount of information (number of layers) the loading time is rather ...
3
votes
2answers
448 views

Batch Convert Folder of GPX to SHP in QGis

I have a few GPX files (up to 35 Mb, with a few tracks each one) that I want to convert to SHP. QGis is faster and easiest, than ArcGis to convert GPX tracks to SHP, but is there a way to batch ...
1
vote
1answer
243 views

TauDEM tools in QGIS 2.10.1 Pisa (Ubuntu 15) are not in the Processing Toolbox

My TauDEM tools have disappeared in my latest version of QGIS. Any ideas how to get them back? They used to be in the processing Tab. Using QGIS 2.10.1 TauDEM Ubuntu 14 stable My other tools are ...