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

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4
votes
1answer
201 views

Ignoring certain data values in graduated maps

I'm working and creating a large amount of maps using the latest version of Qgis with vector files and corresponding data sheets. Usually, there will be missing values which is usually easily avoided ...
2
votes
1answer
79 views

QGIS TimeManager with multiple features at one time?

Since the data I have to deal with is really large, it is not practical to separate every feature into one line in the CSV file. Is there any way to animate them as a whole layer? I have ...
0
votes
0answers
19 views

Learning QGIS Resources [duplicate]

I am mainly an ESRI user but want to begin branching out into opensource solutions. I wanted to start looking a QGIS and was interested to know what other resources people were using to learn the ...
0
votes
0answers
125 views

Equal Area Projection for Indonesia - Standard Parallels

I am trying to do area computation stuff over whole of Indonesia and as such, am using the following projection: http://spatialreference.org/ref/esri/asia-south-albers-equal-area-conic/ To make this ...
1
vote
1answer
117 views

Automatically changing the angle of a symbol in QGIS?

I am working with an iron age cemetery in QGIS. I marked every grave in a point layer with several columns; amongst others, burial rite (inhumation, cremation etc.). I inserted a second column for the ...
1
vote
1answer
122 views

Make diagonal grid in QGIS, divide square into squares

I have square polygon which is aligned under some degree and I want to divide this square to, for example, 25 smaller squares, which must be under the same degree in this square polygon. How this can ...
1
vote
1answer
68 views

What projection to use for many parts of the world

I'm creating a poster which has many separate maps (rivers of the world). I'd like to use a similar projection for each of them, so they're comparable in terms of shape and size. I guess I want some ...
0
votes
1answer
73 views

Where are cpp files from libqgis? [closed]

I am in linux Mint 17.0 I am trying to develop a small application in Qt using libqgis library. When I create a Class inherit from QgsMapCanvas, I get mistakes related with 'undefined references to.....
1
vote
0answers
57 views

Extra white space in ASCII file due to Translate GDAL from QGIS Modeler

Could anyone enlighten me why do I get an extra white space in from of my first column in an ASCII file generated through a model? With ArcGIS it doesn't happen. Output raster type: Int32 Output size:...
2
votes
2answers
428 views

How to run Processing qgis:extractbylocation?

I try to use the processing 'qgis:extractbylocation' in QGIS 2.8.2 from the QGIS algorithm provider. import processing # import the layers by a given uri inputlayer = QgsVectorLayer(uriTr.uri(), "...
1
vote
0answers
18 views

calculating total area of multiple polygons in qgis [duplicate]

I wish to know the total area of all polygons within a shapefile layer. So far I have added a new column to the attribute table that shows me the individual area of the polygons.I tried to copy the ...
1
vote
0answers
71 views

QGIS Convert polygon to point with attributes AND resetting incremental values

Im totally new to QGIS and having trouble with model builder. i am trying to convert polygons to points. Each point must have the attributes of its parent. each point must also have: 1) an ID that ...
1
vote
1answer
317 views

How to split polygon features using an overlaid polygon layer in QGIS?

I have a polygon layer (pictured below) that I made by vectorizing a clip from the USDA Cropland Data Layer. The low resolution of the USDA layer causes fields that are separated by narrow roads to "...
1
vote
1answer
233 views

Setting transparency of layer group with Python in QGIS?

How can I set the transparency for all layers within a group of layers? I assume this will require the use of a FOR loop in the Python Console. Based on How to set the transparency for multiple ...
1
vote
0answers
103 views

Georeferencing reversal of image

I georeferenced a map and it posted to canvas as a mirror image of the original map. I set my project CRS before starting and also made sure to set the same SRS for the Geotiff being created and saved....
0
votes
1answer
87 views

Assigning circle colours to map using QGIS?

I am trying to make a map showing which zip codes are served by which hospitals. There are five hospitals and each can serve one or more zip codes. I'd like to show each zip code with a dots of ...
0
votes
2answers
101 views

QGIS - Edit Surface DEM to Add Buildings

Okay, let me start by saying I'm no expert in QGIS, I'm more into engineering. I'm building a 2D hydraulic model and I would like to add the building footprints (elevated) to my DEM, so flow will go ...
1
vote
2answers
107 views

Output Raster r.cost.full values

I am having troubles interpretating the output of r.cost.full. Currently i am working on a project comparing some arcgis tools with qgis tools (workflow and output). One of my examples is to make a ...
1
vote
0answers
57 views

QGIS symbology to ESRI

Does anybody know how to export the layer symbology from QGIS into a format that can be used by with ESRI products? I have been successful in exporting an XML but it quotes the file type as: !DOCTYPE ...
1
vote
1answer
221 views

How can I dissolve adjacent polygons based on minimum attribute value? [duplicate]

I'm trying to merge the polygons (administrative boundaries) in a dataset untill they reach a minimum value. Lets say that the polygon dataset consists of the number of people per polygon and I need ...
1
vote
1answer
217 views

QGIS - How do I stop automatic ANSI_1252 to UTF-8 encoding when adding a DXF layer?

I have a DXF file encoded in ANSI_1252, with object attributes containing umlauts. When I open it in QGIS, the umlauts don't display properly. This apparently happens because QGIS automatically sets ...
1
vote
0answers
585 views

ImportError: No module named sip

I have been trying to write a custom application to generate contour from QGIS. This is my starting code: import os; from qgis.core import *; This is the error i am getting: Traceback (most recent ...
1
vote
1answer
81 views

Column length editing in QGIS or ARCGIS

Can anyone suggest how I can change the length of an existing column (For ex. column name -- ABCD, column_Type -- Text, Length -- 254). It would be great to have solution on platforms like ArcGIS or ...
4
votes
2answers
348 views

QGIS Function editor calculate area after transform

In the QGIS function editor, it is possible to transform geometry using transform(geometry,'EPSG:xxx','EPSG:yyy') - however there isn't an area() function to recalculate the area of this. The reason ...
1
vote
1answer
80 views

Using Advanced Python Calculator in QGIS Modeler

I'm trying to create a column with integer values based on a small function that basically uses conditional statements. In short, a reclassification. My attempt below: def getValue(Etat): if Etat ...
1
vote
1answer
226 views

Installing QGIS on Mac OS X 10.6

Could someone kindly explain how to get QGIS (any stable basic version) on my old Mac (OS X 10.6)? I'm completely new with QGIS and all the instructions that I can find beats me.
1
vote
1answer
42 views

Exporting output in ASCII from a QGIS model

I'm trying to find a geoalgorithm in QGIS's Graphical Modeler that can convert and export a vector to ASCII. Could anyone enlighten me if there's an option for that? Perhaps through some script but I ...
1
vote
1answer
174 views

How to detect coordinate reference system (CRS)? – I cannot display two vector layers in QGIS at the same time!

When I in QGIS try to display layer (a) together with another layer (b) that differ in their CRS it doesn’t work. Both are vector shapefiles. I have tried both with using QGIS ‘on the fly’ CRS ...
1
vote
0answers
71 views

QGIS Pipe Flow and Aerial Photo

I am completely new to QGIS and We had the survey pick for drainage pipes and pits. We have Upstream and Downstream invert level for each pipe. Wondering if any one could help with step by step, set ...
1
vote
0answers
177 views

QGIS - Pop-up menu not displayed when right click on a layer in layer tree view

I'm developing a custom QGIS application using the QGIS API. I've been using the API provided with QGIS Brighton (Version 2.6.1) and have been developing the application in Python in a Windows 7 ...
1
vote
1answer
123 views

Problem with writing input and output for QGIS user script

I need to write QGIS script, which removes features with same value of specific attribute - in output will be only features with first occurrence of value. I know, how to check duplicity, but I don't ...
2
votes
1answer
263 views

QGIS fails to clip and produces empty shapes

I've seen this type of question a few times and have tried all the different suggestions but no luck. I have 2 layers, one polygon and one line. I want to keep the lines based on a selected polygon. ...
2
votes
1answer
162 views

QGIS working directory

I was just wondering what's the best way to organise QGIS projects. My problem is that I work across different platforms, Mac, Win and Linux and the project contents are stored with links to the files....
1
vote
2answers
96 views

Interactive “for each item in … do …” in QGIS?

How does one interactively run a basic looping batch construct in QGIS? for each {feature} in {features}: do {thing} with/to {feature} save/export/display {result} Where: {features} ...
0
votes
0answers
37 views

Number of intersected features from one layer per feature from second layer

How can I get number of intersecting features from one layer per feature from second layer using any component from QGIS 2.8 (GRASS, SAGA, Python scripting...)? Result should be stored in new ...
1
vote
1answer
334 views

Is it possible to use non-printable characters as delimiter for text file layer in QGIS?

I am trying to import a Delimited Text File Layer from a .csv file in QGIS. Because this caused a lot of errors, I posted a question here and got the hint towards using ASCII non-printable control ...
2
votes
1answer
47 views

How to change decimal places when using graduated renderer?

The classifications given when I use the graduated renderer on QGIS under 'Layer Properties' are to 4 decimal places, and I would like none. I know I can use the rule based style and create my own ...
3
votes
1answer
103 views

How to change the “application_name” of a PostGIS-connection in QGIS?

PostGIS offers a view called pg_stat_activity, where you can see all the active connections to the database. This view includes the interesting column application_name. When a connection comes from a ...
2
votes
3answers
125 views

Strange coordinate system [closed]

Here's an extract of a feature from the web that I converted to geojson using qgis. However, the coordinates are not standard are at all and when trying to actually preview it on the web it fails, ...
2
votes
1answer
141 views

PyQGIS: How to get the list of valid layers in TOC?

To get the list of TOC layer names I used the approach suggested here: for layer in QgsMapLayerRegistry.instance().mapLayers().values(): print layer.name() But this method is not reliable due ...
1
vote
2answers
174 views

Is it possible to split a picture taken with a regular digital camera into real spectral RGB channels?

I have no idea how the sensors inside a camera work. I know I can take jpeg and separate the R, G and B channels but I have no idea whether these channels are the real red, blue and green in visible ...
1
vote
1answer
145 views

How to remove group filter applied via Python-console (setSubsetString) of QGIS?

I need to quickly applie (and then change/remove) the same filter for about 100 layers in my QGis project (all put together in one group). Since there is no implemented solution right now (a feature ...
1
vote
1answer
32 views

Adding New Linear Feature using QGIS?

I am new to QGIS (2.6.1) and am having trouble adding a new linear feature to an existing layer. I have set tolerances and digitized the vertices of the line and it terminates with a large green X at ...
2
votes
0answers
77 views

Create a sript for “point sampling tool” of QGIS

Is there any way to create a python script to the "point sampling tool" plugin from QGIS? I have a very large number of Netcdf files which I want extrat the values from pixels to a irregular points ...
0
votes
1answer
69 views

in a single vector layer I have a three of polygons with different field values (e.g1,2,3). How Can I color each field value polygon differently?

In a single vector layer I have a three of polygons with different field values (e.g1,2,3). How Can I color each field value polygon differently? To explain a bit more my three polygons are showing ...
1
vote
1answer
81 views

Bing Aerial metadata in QGIS

I am using Bing Aerial imagery within QGIS through the openlayers plugin. How can I find the dates of the images that are within the map canvas? Thank you Becky
1
vote
2answers
328 views

Is it possible to not show node in editing mod QGIS

I actually have a plugin that allows me to draw on a vector layer (I made it based on the FreeHand Editing Plugin). When a mouseMoveEvent is detected, it creates a new point on the vector layer and ...
0
votes
0answers
47 views

QGIS File Geodatabase Vertices missing

I am adding Data from a File Geodatabase to QGIS. Everything is working fine, but the drawing of a specific Line subtyp (first image). It looks like, QGIS can not draw the circle properly. An export ...
2
votes
2answers
888 views

QGIS 2.8 starts with an error and I am not able to run Python console

I have installed QGIS 2.8 - Wien on Linux Red Hat 7. Unfortunately when I start the application I got this python error: {Couldn't load plugin 'processing' from ['/usr/share/qgis/python', '/home/...
3
votes
2answers
154 views

Need a vector format that is editable in QGIS and supports >10 character column names

For reasons, I need to create a new column in a vector shapefile with a name longer than 10 characters, and export to mapinfo TAB format. I know .shp's don't support >10 character column names, so I'...