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

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2answers
202 views

QGIS opening file - Very slow on POSTGIS databse with many layers

When opening a qgis file with many layers (20 or so) it takes +5 minutes to load. All the layers come from a single PostGis database. When looking into the server logs, i see that there are many ...
1
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1answer
285 views

How to link my QGIS plugin main class to mouse events from a custom Tool?

I Have two files one is mouseevent.py and the other one main.py. class MouseClick(QgsMapTool): canvasDoubleClicked = QtCore.pyqtSignal(object, object) def __init__(self, ...
2
votes
1answer
202 views

Generate new geometric network from intersection between curent network and polygons

Ok I've been battling this one for a little while. I have generated a stream network using the "Strea Reach and Watershed" tool from the TauDEM toolbox. Within the stream reach dataset there are ...
0
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1answer
234 views

export to GeoJSON coordinates in the reverse order

This question has been asked before, but I don't understand how to use the answer given by cengel. I want to make a GeoJSON file with lat long coords, not the default of long lat coords. I have a ...
3
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0answers
71 views

Integrating numeric scales into a text or HTML box in QGIS print composer.

I am trying to embed the scale of a map in the print composer expression builder or HTML frame. Effectively the value of the scale in the map item properties would come through into the text and be ...
5
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2answers
7k views

Installing QGIS 2.6.1 on Ubuntu 14.04

First I am relatively new to linux particularly Ubuntu 14.04 so if you intend to help me, just indicate the exact commands (step-by-step) that i need to type to get QGIS 2.6.1 Installed I have tried ...
1
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1answer
45 views

What's the letter and word spacing unit in QGIS labeling?

I just want to know if letter and word spacing, in qgis labeling, are expressed in points, and if the value its absolute or relative to the font. I have searched a lot, but I can't find any ...
3
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2answers
401 views

great circles in QGIS and export in 3857 webmap

My plan is to visualize great circles in a leaflet webmap. So coming from this great postgis article and R version I thought it would work like this in QGIS: create line from two points, store ...
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0answers
42 views

“mapinfo qgis style converter” : error message

I would like convert a big point layer from .Tab toward .QML thanks to the plugin called "mapinfo qgis style converter" . The symbology of my layer is quite complexe (variables of coulours, shape, ...
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2answers
325 views

How to delete a shapefile from a directory using QGIS?

I am using the following code to clip a shape file using processing tools via Python and would like to delete the clipped file from the directory. Here is my code. from PyQt4.QtCore import * from ...
1
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0answers
353 views

qgis-bin.exe has stopped working after changing symbol selector?

i am having troubles with QGIS 2.6.1. It crashes when i try to change the symbol selector within each vector layer. If it doesnt crash it seems that the changes i have made in symbol selector do not ...
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0answers
19 views

How to fix the links clipped by an unconnected area in QGIS?

I'm trying to clip my target shape file with a given example area. The given example area looks like the following pic: And there is a river separating two areas. However there are links ...
2
votes
2answers
64 views

Why do I get green crossed circles instead when I try to move a point?

It's really horrible I must say. I sometimes have geometry issues and then try to go one by one through them and fix these cases. Therefore I mark the area points and delete them for instance. After ...
2
votes
1answer
110 views

Is there a way to give the drawing red polygon a higher alpha channel

Is it possible to set the alpha channel a bit higher when drawing? I don't mean the alphachannel of a already finished polygon, that's possible for sure! I mean the red area. It's really stressful ...
4
votes
1answer
797 views

How to clip a single layer of overlapping polygons in QGIS

I have a single layer of polygons. Some of the polygons overlap. I wish to make a new layer of just the parts of the polygons that overlap. What is the best way to do this in QGIS seeing it's ...
1
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2answers
105 views

Is it possible to redefine a projection in QGIS?

Is it possible to redefine a projection in QGis? It seems like the shape files offered by Agiv (a Flemish agency) differ slightly from the definition that QGis has of EPSG:31370. I'm NOT looking to ...
4
votes
3answers
429 views

Calculating file name with field calculator

Is it possible to calculate the file name in an attribute table? My shape file has a name like "cities.shp". In this shape file I want to have a attribute "cities").
2
votes
2answers
54 views

Clipping polygons within a certain range

I have a map consisting of polygons and a line. I need to a new shapefile of polygons that are to the west of the red line, and are between the northmost and the southmost ends of the line. How can I ...
5
votes
2answers
135 views

Why does qgis give multiple centroids per polygon?

I have a shapefile for the boundaries of European NUTS regions, and I would like to compute the centroid for each of those regions. When I do this in QGIS (2.6.1 on OSX, using polygon centroids from ...
1
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2answers
251 views

MultiLine field-name label referencing

A labeling routing (which is updated often) is being implemented via pyqgis and a QComboBox. The attached code below worked great, that is until needs for narrowed column headers spawned the use of ...
1
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1answer
88 views

Edit an old georeference raster projection in QGIS

I have created a map from a picture. And now I have some more detailed pictures and georeferenced them. Is there any way to quickly access them later on. I mean everything is fine with ...
0
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0answers
40 views

QGIS multiply(add) two raster but divide(deduct) another raster

I am making a parking analysis in one town. I need to obatin the zones where the parking of car is harder because there is less places to park and higher demand of cars.I have three rasters. First ...
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1answer
42 views

How to update the value of a field dependant upon the the fields ID in QGIS Field Calculator

I am looking to create links to website pages and to automate the procedure a bit more I would like to have a standard link followed by the ID of each field. For example, I would like the standard ...
1
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3answers
856 views

How to split a line every x meters? [duplicate]

I have a line that I ultimately want to split up into points. The points should be every 100 meter along the line. So I don't want to extract the nodes. Are there any OpenSource (QGIS, Python) tools ...
2
votes
3answers
148 views

Prefixing multiple values within QGIS using the Field Calculator?

I have a column in my my attribute table that contains a series of individually numbered locations. I wish to prefix all of these numbers with a letter, this letter will be the same for each of the ...
2
votes
1answer
167 views

Simplify a polygon dataset with a minimum distance between the new vertices

I would like to simplify a polygon shapefile where the resulting output has a minimum distance of 5 kilometres between the new vertices. We have ArcMap 10 on an ArcView license, FME and QGIS. I have ...
3
votes
2answers
134 views

How to compare a classified raster dataset to another polygon dataset?

I am going to perform an unsupervised classification on my dataset and will get a map as a result. The objective is to rebuild an already existing map (of different soil types) with my new dataset. ...
1
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1answer
83 views

Load Oracle Spatial Raster using PyQGIS

Able to connect to Oracle Spatial 11g and print tables with SDO_GEORASTER attribute both in QGIS python console and standalone application.I get below error when loading rasters from oracle Table. ...
0
votes
1answer
102 views

Merge two points of two different polygons to get one polygon at the end

I would like to join points from two different features. I already searched for plugins but so far but didn't find one working plugin or solution for my task. So here is a picture of 2 ...
0
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1answer
82 views

Calculate shortest path not on land but over sea

I wonder if someone can give me some advice on how to calculate the shortest path between two points, not over land but over sea. I know that I will have to take in to account the magnitude of sea ...
0
votes
2answers
65 views

Number shape files

Is it possible to number shape files? Before merging the single point layer I want to give them numbers. After filtering the merged files I need to split them (the number should be a marker for the ...
1
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1answer
35 views

Reordering of layer properties fields in QGIS possible? [duplicate]

I'm wondering why such simple things are not possible. I have 5 fields on my layer and the last one shall be on the top now. But there is no way to do this, is this correct?
2
votes
1answer
92 views

How does the QGIS construct class intervals?

I'm using graduated style of a point layer to assign a colour ramp to symbols (squares). I assigned manual values to class intervals specifying classes to be: 0.60 - 0.80 0.80 - 1.00 That is, in ...
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1answer
144 views

Unable to draw a polygon due to “The feature cannot be added…”

The feature cannot be added because it's geometry collapsed due to intersection avoidance. see also http://i.imgur.com/xiiI7NE.png What happended: Let's say I have 2 layers. To the first I ...
0
votes
1answer
82 views

Calculating distance between previous and current addresses for large file

Hoping to get help with this. I'm a fairly new QGIS user and trying to solve the following problem: Let's say I have a large dataset (5000+ records) of customer addresses, previous and current, and I ...
2
votes
1answer
186 views

Load PostGIS or Oracle Spatial Raster Layer using PyQGIS

How do we load Rasters stored in PostgreSQL-PostGIS or Oracle Spatial 11g into QGIS using PyQGIS? I am able to load vector layers from Oracle 11g with below code. What changes are necessary to add ...
6
votes
4answers
595 views

How to Unsplit/Dissolve multiple touching lines in Stream Network?

I am trying to dissolve multiple lines for stream networks into individual features. The dataset contains many stream networks so a complete dissolve of the whole dataset wont do as I would like to ...
2
votes
1answer
70 views

Is there a way to disable right-click in QGIS when drawing

I would like to know if I can disable the rightclick in QGIS. The issue is that I draw polygons that are kind of big, let's say 4000 polygon points. And as you know rightclick brakes the drawing ...
2
votes
2answers
142 views

QGIS Layer Style - Adding intensity/color if elements overlay

I have a layer with thousands of points. I have been asked to represent this layer in way that can be easily seen the level of concentration of points in the layer. So when there is much point ...
1
vote
5answers
3k views

Getting No module name exifread error from QGIS Photo2Shape plugin?

I had Photo2Shape plugin installed on QGIS 2.4 (Windows 64 bit), following installation of 2.6.1 and an upgrade of the plugin itself Photo2Shape is now broken. Error message on install is "No module ...
4
votes
1answer
230 views

How to show Python console at QGIS program start

I wonder if there is a way to open the Python console of QGIS 2.6 directly at program launch. There is a possibility to set a shortcut for the Python console, but I can't find such an option for the ...
0
votes
0answers
33 views

How to georectify a fictive earth to a projection-less version

I have a picture of a fictive earth-like world. Now I would like to draw the outlines and then georectify this to a projection-less version. I really need the map unrectified. Because I want to ...
1
vote
3answers
244 views

Using QGIS2Leaf plugin to export into leaflet but output results into browser crash?

Amateur GIS technician here, Just tried to export my converted cad cities pipelines into a shape files and then export it into leaflet using QGIS2Leaf but the browser crashes before the displaying the ...
3
votes
1answer
50 views

From LiDAR .txt to QGIS map

I have Lidar data in .txt files (1000 to 26000 KB), where 2nd column marks x-coordinates, 3rd col y and 4th col z. 8 485000.16 6508997.48 1.84 66 Last 2 485001.27 6508998.92 1.86 82 Last 2 485001.02 ...
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1answer
78 views

How to snap polygons to lines?

How can I snap a polygon to a line? For example, I have a polygon which represents some meadows to snap over a line which represents a road. Thanks! Dani
3
votes
1answer
609 views

How to snap lines to nearest point?

Is there an easy way to snap lines to nearest point of either a line or a polygon? I don't see any snapping options for line layers as suggested on How to merge lines with slightly different endpoints ...
2
votes
2answers
206 views

Project house on WGS84

I have imported a DXF file of my house in QGIS. I also included an openstreetmap layer in WGS84 which also displays my house as a square. Naturally, my house from the DXF file is placed in the ocean ...
1
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0answers
22 views

Merge based on joined attribute in QGIS [duplicate]

I have a single layer of polygons (drawn around every zip code). I have a CSV file with territory numbers and the zip codes in each territory. I joined these and was able to color each territory ...
1
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1answer
95 views

Export from QGIS to Google Maps maintaining formatting

I'm totally new to QGIS so I'm not even sure this is possible. I've created a bunch of polygons within QGIS and they look just like I want them (color, transparency, etc.). What I'd like to do now ...
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0answers
21 views

Is there a QGIS equivalent to ArcGIS's Make OD Cost Matrix Layer (Network Analyst)? [duplicate]

I'm looking to create a OD cost distance matrix for a network data set I have created. Is there a way of doing this in QGIS which is akin to Make OD Cost Matrix Layer within ArcGIS's Network Analyst. ...