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

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99 views

Determining Projection using QGIS?

I am very new to QGIS and I am trying to determine the spatial projection and the units of distance of a certain raster file. The closest thing I can find is the CRS, which is set to some sort of ...
2
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1answer
2k views

convert vector (point shape) to raster (tif) using python gdal lib in qgis

I'm trying to convert a vectorlayer (point- shapefile) to a raster-dataset (tiff) using python gdal-library in qgis. On Graphical UserInterface I simple choose the menue "raster->conversion->...
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1answer
403 views

How to trigger a QGIS action when a plugin button is clicked?

I tried calling the select free hand tool by below snippet of code. iface.actionSelectFreehand().trigger() I dnt have any idea how to call this when i am pressing a button in GUI. my gui is ...
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65 views

Error in my buffer plugin

In my buffer plugin, i tried the following code # Get buffer distance and selected city dist = float( myLineEdit.text() ) city = myComboBo.currentText() # Get the feature corresponding to the ...
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0answers
146 views

Which version of the Oracle Client do i need to get Oracle support in QGIS 2.6.1?

I have just installed QGIS 2.6.1 and wish to connect to our Oracle Spatial 11g Database. Am I correct in thinking I will need the Oracle Client installed on my machine for this to work? If so which ...
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0answers
55 views

Is there a way to (helpfully) give feedback on QGIS Training Manual?

I'm just working my way through some of the current QGIS Training Manual: http://docs.qgis.org/2.6/en/docs/training_manual/ As I work through it I am coming across occasional things which are out-...
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1answer
178 views

Problem with creating a model in Qgis — select by location

I have two shapefiles (polygones) - referentiebestand and oudejaren -> the first step is to calculate the centroids of each shapefile (gives a good result), then a create a buffer around one of this ...
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1answer
200 views

How to call default tool in QGIS inside plugin using python script?

I want to create a plugin which can draw irregular polygons in QGIS. For that, I want to call the Select features by freehand default tool inside my plugin. How can I do this within a python script?
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1answer
266 views

How to connect Excel file with QGIS?

I am working with QGIS and I want to connect with Excel. I have exported attribute tables to Excel. Now I want to connect Excel with QGIS in the way that if I change a line dimension, it will be ...
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0answers
22 views

How to highlight joined features?

I have a task in QGIS (2.6), where I need to join two tables through an action (I think). I have some projects (points) that I need to connect to a list of partners (also points). I have data in both ...
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0answers
123 views

Mask plugin, Atlas composer and Legend

I'm tryin' to use the mask plugin associated with atlas composer (QGIS 2.7 dev). I'd like to have in the legend of map composer only the features that belong to mask instance (inside the mask). if I ...
2
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1answer
833 views

Split polygon into several smaller polygons in QGIS

I have a layer of polygons depicting response boundaries, I would like to break each of these polygons into a number of sub-polygons. As this is for an exploratory project, the polygons themselves ...
3
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1answer
103 views

Export DXF Issue in QGIS?

I got the shapefiles in QGIS and transformed them to UTM NAD83 from WGS84, then tried to create a DXF of it so I could use it as an overlay in fieldgenius software for a topographic survey we're ...
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2answers
416 views

QGIS (2.6.1) Processing Toolbox InitGui error after changing /Users folder on Mac OSX

Using: Mac OSX 10.9.4 QGIS 2.6.1 I had previously installed QGIS and had everything running fine. My home directory was /Users/rowanbado, but for another application I had to add an ...
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0answers
405 views

Why are OGR (MySQL / PostGIS) connections extremely slow in QGIS 2.0 - 2.8 (when compared to QGIS 1.8)?

In our project we have been using QGIS 1.8 Lisboa with a MySQL database placed on a server accessed via local network since two years. Everything is working fine and quick. The vector layers can be ...
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0answers
40 views

Network Analysis for Pickup and Dropoff

I have a bit of a problem that I need help with. I am looking at a set of lat/long with a time stamp for the desired pickup or drop-off for passengers. There are multiple pick-ups and drop-offs within ...
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3answers
329 views

Is it possible to set up a local QGIS Plugin repository?

I've developed a couple of custom QGIS Plugins for use by our office. I can't post them to the official QGIS Plugins repository as they reference/utilize sensitive data on our own servers. For ...
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0answers
36 views

QGIS How to multiply (repeat n times) a point by field [duplicate]

I have a point layer in QGIS that has a field named "Amount" that stores an integer value for every point in the layer. I want to create N points in the exact place of the feature that has N as ...
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1answer
184 views

print composer and atlas feature on large dataset

this question could be very complicated, so I'll try to be as clear as I can. I have a polygon (hundreds of cells) that has a quite rich attribute table (more than 30 fields). Each field contains ...
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2answers
58 views

Is there a list of free application modules (or “Fachschalen”, in German) for QGIS somewhere?

I'm looking for application modules (in the form of plugins) that cover sets of related tasks like asset management, in a basic UI. A simple use case example: a water gauge (point feature with a 1:n ...
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1answer
213 views

Run C++ standalone application in debug mode

I write simple C++ standalone application using QGIS. It works and render vector layers from PostgeSQL database. #define CORE_EXPORT __declspec(dllimport) #define GUI_EXPORT __declspec(dllimport) #...
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4answers
14k views

How to export attribute table to Excel from QGIS?

I have seen all the questions for this question, and I try all the answer like copy paste, csv (in fact this I don't know where to find) but none of all is not the right answer. Can anyone help me?
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1answer
311 views

How to enable the snapping for a layer with the tolerance value with python programming

I have a vector polygon and vector polyline layer. I want to enable the snapping for both the layer with tolerance value? How can i do that using python programming. I have tried this code but getting ...
2
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1answer
106 views

Create a grid with statistics of the merged shapefiles in QGIS

I operate with QGIS. I have to split the shape files of the buildings and the roads of a city into a grid of 500x500m per square and into each square I have to obtain the total free area, the total ...
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59 views

How to project the geographic grid in a shapefile in QGIS

Is it possible to automatically project the geographic grid (View -> Decorations -> Grid) into a shapefile layer in QGIS?
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1answer
664 views

How to save the Map Canvas as PNG with transparent background programmatically?

I wrote a script to create a big number of heatmaps for a given scenario. I would like to save the result of every heatmap as a png image. I have figuered it out doing it with simple Map Rendering but ...
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0answers
152 views

QGIS 2.6 SAGA Processing Algorithm, “Add grid values to shapes”, produces NULL Values

I'm using QGIS 2.6 Brighton on Windows with SAGA 2.0.8 installed using OSGeo4W. I have the same versions installed on OSX as well which is not having this problem. On Windows, I'm trying to extract ...
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0answers
58 views

Getting coordinates from random directions

This is an odd question, but was wanting to know if there was a way to get coordinates from random directions. I have about 2000 directions in a spreadsheet column. There is name and a few other ...
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79 views

Line length for line files

Using QGIS, Brighton 2.6. Trying to calculate line-lengths for linear features (roads, trails, fenceline) and used this post (How to find line length in QGIS while editing?) and the links associated ...
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1answer
54 views

How to display symbols on a Raster in QGIS?

I have a raster file in which each cell has a numeric code which indicates that the cell is directed towards one of its eight neighbours. I am using QGIS to display each of the eight possible codes ...
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1answer
29 views

Projection issues with merging files. [duplicate]

New QGIS user, 2.6 Brighton. My project CRS is default to Nad83ft / N.Carolina (US). I loaded various polygon and line (provided to me) that have various CRS's but they still show correctly in place ...
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1answer
212 views

QGIS gets stuck when running script to automatically refresh layer [closed]

I have a QGIS layer that represents a set of links and nodes to show the streets of a city and the traffic speeds on each street. I've been trying to write a script so that if I change the speeds in ...
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1answer
103 views

Why is the display of QgsMessageBar delayed?

When a function is called - a file is tested for existence. This checksum pushes a messageBar() object for both circumstances (True/False), yet the actual bar does not display in MapCanvas until ...
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1answer
143 views

How to exclude a certain attribute from being added to the Processing script output layer?

I have a working script to split a layer by field attributes and save the single features as files: ##[User scripts]=group ##input=vector ##class_field=field input ##output=output file from qgis....
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1answer
55 views

How to remove a parcel from a larger area?

New QGIS user here. I'm trying to clip a large (2000-ac) property boundary with a smaller (500+/-) acre property. Assuming the larger boundary is the input layer and smaller is the clip layer, my ...
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0answers
463 views

Couldn't load plugin processing in QGIS: Access is denied for R

Couldn't load processing plugin due to flowing error. Any help? thanks. Couldn't load plugin processing due an error when calling its initGui() method Traceback (most recent call last): File "C:/...
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0answers
61 views

Hydrological triangle (geoscience) with QGIS 2.6.1

I want to interpolate ( TIN-Interpolation) between variable points (the best within a triangle) WITHOUT producing new shapefiles (or csv data file). So what I have now is an interpolation of all ...
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0answers
76 views

Is there any way to create user login for single project in QGIS?

Is there any way to create user login for single project in QGIS? I want to track changes on database when users update features. I know that I can do this on database level but is there way to do ...
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1answer
303 views

How to calculate distance to polygon edge to compute building setbacks?

I'm trying to calculate building setbacks using building footprint data. A building setback is the distance between a building and the edge of the lot line. (You can distinguish this further—garage ...
2
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1answer
2k views

Can QGIS or GRASS convert layer files to shapefiles?

Should I be downloading QGIS or GRASS? I want the program with the most features. Most importantly, I have a lot of .lyr files. Can either of these softwares convert to shp and if so, how can I do ...
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1answer
145 views

Tools for map animations

I am preparing some visualizations of data (mainly animated choropleths), and I am looking for suitable tools. Ideally, I am looking for something similar to this kind of animated infographics. So, I ...
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0answers
264 views

How to show elevation on mouse hover in QGIS?

I've got a DEM layer and would like to have the status panel in the bottom display the elevation in addition to the mouse coordinate. Can that be done? Using QGIS 2.6.1
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130 views

Polygon vertex “duplication” in QGIS?

New QGIS user, Brighton 2.5. When creating or moving new vertex points of a recently-cut polygon (hence adjacent polygons) I get "duplicate" or "criss-crossed" lines beneath the former vertex ...
3
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1answer
715 views

How to match a raster NetCDF data with a vector layer in QGIS?

When I load a raster layer with humidity data from NOAA database (for instance rhum.2m.2014.nc at ftp://ftp.cdc.noaa.gov/Datasets/NARR/Dailies/monolevel/) I am not able to match it with a simple map ...
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1answer
47 views

How to access layer in QGIS?

I want to get QGIS to update from a CSV file like in this How to update data from external table in real time? question, however I can't figure out what to put for "myLayer". How can I define the ...
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0answers
127 views

Polygon Layer Cleaning with QGIS

I have a little situation with my data. I have vectorized a raster layer, and now I have some issues with the geometries, as you can see in the picture. Most of errors I have are like this one. ...
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1answer
66 views

How to find length attribute form my all lines in my layer

I am a begginer for QGIS I have a column for the length of the lines, but don't know how to find it. Can anyone help me?
2
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1answer
211 views

How to unlock imported GeoJSON vector layer?

I have a map on geojson.io, with some fails that I need to correct. It has a feature to edit polygon's node but it's too tedious and hasn't "snapping" mode. So I've imported my .geoJSON, .shp, ....
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0answers
59 views

How to export only labels as svg in QGIS 2.6?

I'm working with a big big data set in QGIS 2.6 (but also in QGIS 2.7). I have many line layers styled with the rule rendering tool. What I want to do is to export only the labels of all these line ...
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0answers
99 views

What's the best way to convert points to raster and back again?

To convert raster grids to vector points In QGIS there we have different possibilities (grass tool "to.vect"; saga tools "grid values to points"). My problem is a little bit complicated. In the ...