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

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75 views

gdal_translate from within pyqgis [duplicate]

I want to use gdal_translate from within a python script in my plugin qgis2leaf. I've tried with ...
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1answer
58 views

QGIS: Turning Filter On and Off

When a filter is applied to a layer the layer cannot be edited. Is there any way of quickly turning the filter on or off without entering the Query Builder dialog box and removing the filter?
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0answers
36 views

How can data of columns of the attribute table be refreshed automatically?

I can't find a solution for an auto-refreshment of attribute table data. F. e. does the data of a shapefile-object (f. e. field calculator - $area) not change, if the geometry of the object is ...
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1answer
104 views

Qgis - unwanted offset when using raster interpolation plugin

I'm using QGis and I have a set of points with a depth attribute. I'm trying to make an interpolation using the Raster interpolation plugin (Raster -> interpolation -> interpolation). But when I do so ...
9
votes
1answer
741 views

How can I improve the speed at which QGIS 2.4 handles network data? (Seems much slower than 2.2 - even with small datasets)

I recently downloaded and installed QGIS 2.4 Chugiak on a Windows 7 64-bit machine with a quad core processor and 8GB RAM. I'm having a few problems using datasets of all sizes from a network drive - ...
1
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1answer
99 views

Resampling with Python console (QGIS): number of parameters

I am trying to resample two raster layers with Python console in QGIS with this code: outputs_0=Processing.runAlgorithm("saga:resampling", ...
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0answers
45 views

Changing original source projection

I am attempting to match up 2 raster layers, both a OS survey map and some independent survey data. The map I know to be in the correct position, However the survey data shows a layer extent of (layer ...
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0answers
110 views

Exporting SHP files into Autocad readeable files

I have a full water supply network drawn in a shapefile which I created using Qgis 2.2.0. Now I need to export it into a format that enables me to open it in AutoCAD. I am trying to export it as a dxf ...
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0answers
254 views

How to force geometry type in (WFS) layer in QGIS

I have an external WFS source serving mixed geometry types - in other words, I have no control of the source. When adding the layer QGIS sets the geometry type to line and thus I am unable to style ...
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4answers
1k views

Cheaper solution for uploading maps to GPS (forestry maps: roads, trails, hydro, polygons)?

I'm using a QGIS 2.2.0 Valmiera on a Windows 8.1 system Desktop. I'm a forester and I would like to have a cheap solution to load maps into the handheld Garmin 60, 62 or 64 series GPS. Free would be ...
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1answer
104 views

how to select line segments not overlapped by other layer's lines

I have two shapefiles of forest roads (mostly dirt) from different sources, covering the same area. The goal is to build one shapefile of roads that is the composite of the other two. Layer A is ...
2
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1answer
211 views

How to use the MMQGIS plugin through the Python console?

I know how to make Hub Lines using the GUI, I want to know how to do the same using the Python Console, a tutorial would be great. Thank you
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0answers
7k views

Open Layers Plugin and QGis 2.4 [closed]

I have installed Qgis 2.4 with the stand alone installer and the OSgeo4w too on three different computers. Two have win7 64 and one vista 64. It seems that the Open Layers plugin does not work ...
1
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0answers
118 views

Is there a way to QGis read an SDE.ST_GEOMETRY field?

this is the type and name that Qgis displays for me when I connect with a oracle table,it is not displayed as a geo column, there is a setting I'm missing? Can Qgis Read this type of data?
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1answer
405 views

Using Union on multiple shapefiles to output single result

Using QGIS 2.2 and Python, I would like to use the Union algorithm on multiple shapefiles (contained in a folder TEST) which would then produce single shapefile containing all the data. Currently ...
2
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2answers
241 views

How to switch to edit mode vector layers, in pyqt application based on qgis?

I do QGIS based application, I need to implement the ability to modify the geometry of vector layers in manual mode (editing nodes), how to do it?
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0answers
225 views

How to extend lines from “station line” plugin in QGIS

I'm trying to create cross sections using the station line plugin (and then import them to HEC RAS). But I can't seem to create lines longer than 99.99 meters from each side of my river line. Is this ...
2
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1answer
111 views

Low quality legend symbols in QGIS

The legend symbols in my QGIS map composition render very pixelated, like this: However, they render fine for actual point data. They appear this way within map composer, when printing, and when ...
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1answer
91 views

QGIS copy and paste error: “no features could be successfully pasted”

What does this error message mean, and how can you get more info on what might be the cause? "no features could be successfully pasted" (or more generally, not all of the selected items could be ...
1
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1answer
87 views

Why is interpolation adding too much heat

I am interpolating geo data using qgis. The data is in the form of lat,lon,count. The path of the collected data is shown as a mostly transparent line. The resulting heatmap it produces is shown. ...
0
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1answer
140 views

from Qgis 2.2 to Garmin Base Camp: how to get rid of the white frame?

I have geo-referenced a raster map in QGIS 2.2 (with the georeferencer plugin) and I can also create a kmz file for my garmin (Dakota20) with GarminustomMap. However the kmz file, as imported in Base ...
2
votes
1answer
185 views

How to exactly georeference in QGIS

When I georeference a raster image in QGIS, it's always a bit displaced as in the attached image (the cyan polygon is the template, the red border is the georeferenced image), although I try to set ...
2
votes
1answer
181 views

Maximize clusters of points from coordinate data

So I am definitely new to the GIS world, so bear with me if I don't know the best way to articulate my problem. That said, I am ready to learn, I would definitely welcome any direction that you all ...
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2answers
2k views

“Missing dependency.This algorithm cannot be run :-(” QGIS + GRASS Windows 7

Windows 7, OsGeo4W pack installed including QGis 2.4.0 and GRASS. I Qgis when i try to execute a GRASS geoprocessing algorithm i get this popup: "Missing dependency.This algorithm cannot be run :-( ...
2
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0answers
235 views

How can I label the pie charts in QGIS so the labels are written under the diagrams?

How can I label the pie charts in QGIS so the labels are written under the diagrams? My pie-charts are representing localities: such as villages, towns, cities. So, I want that their names appear ...
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0answers
227 views

Why can I not publish from -QGIS Geoserver plugin?

I am following the tutorial at http://qgis.boundlessgeo.com/static/docs/quickstart.html and I get to the step "To publish the project as it is, just select the QGIS project entry in the OpenGeo ...
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3answers
190 views

How to complete the roads output of PostGIS?

I converted the file I exported from OSM to PostGIS using osm2pgsql. I have opened the table's outputs to QGIS and I saw data are not complete compare to OSM editor view. Most of the roads are broken ...
9
votes
1answer
342 views

How to call the interpolation plugin from the python console?

I would like to call the QGIS interpolation plugin function (TIN method) (Raster->Interpolate) from python console. I can't find the corresponding function within QGIS API or within the ...
2
votes
1answer
163 views

QGIS contour plugin exception struck help

I am a fisheries biologist and I am just getting started with QGIS. I took a few GIS classes in college so my GIS knowledge is not extremely high. On to my question. I am trying to make a depth map ...
3
votes
1answer
322 views

How to open, modify and save a QGIS project with PYQGIS

I need to create a stand-alone script for opening a QGIS template project, modify a layer data source, export the Composition and finally save the modified .qgs project into a new file. So far I have ...
1
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0answers
65 views

PostGIS points to multipoint error

I have a table on PostgreSQL 9.2 ("POSTGIS="2.0.1 r9979" GEOS="3.3.3-CAPI-1.7.4" PROJ="Rel. 4.8.0, 6 March 2012" LIBXML="2.8.0""). This is it: CREATE TABLE nearest_point ( id_nearest_point serial ...
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0answers
559 views

PyQt resources file to display images on QGIS custom feature form

I am having issues creating a PyQt4 resources file to display images in my QGIS 2 custom feature form using Windows XP. These are the steps I followed: -Added QLabel and clicked "choose resource…" ...
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1answer
169 views

PyQt QTableWidget for QGIS python plugin: infinite loop issue

I'm using PyQt4 and Python 2.7 to develop a plugin for QGIS 2. I have QTableWidgets used to display/compare existing information in the database with newly entered information pertaining to the same ...
2
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2answers
88 views

Cropping with GDALWarp in QGIS

I followed this post, the first answer, to clip a USGS Quad in order to remove the borders so that I can tile them. Basically it utilized the lat/long at the corners in a .txt file to import a ...
-1
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2answers
127 views

How can I project a power line net in QGIS?

I am working with power lines net using the software QGIS. I would like to know which plugins or tools do I need to be able drawing (projecting) them.
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3answers
80 views

How to set a coordinate transformation GRID

Does anyone know how to set a coordinate transformation in qgis so I can measure the distances in meters or kilometers? If anyone has a clue, would be just great. Thanks!
1
vote
1answer
385 views

Why do I get an error when I try and clip a shapefile to a shapefile using ogr2ogr?

I want to clip a shapefile to a shapefile. The input shapefile is a 1 m vector grid generated in QGIS. The tile I'm clipping to is just a simple polygon (the geometry is contained within the 1 m ...
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0answers
153 views

How to create .dem file in QGIS?

I have an elevation data in .asc file, but need to convert it to .dem file to later use in COMSOL. However, in Raster--> Analyzes-->DEM I got just error message: ERROR 1: DEM Default Setup: Importing ...
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1answer
187 views

Possible to run “Merge shapefiles to one” algorithm from Python script?

Developing a python script in QGIS 2.2, I can run algorithms from the Processing plugin fine such as those from QGIS geoalgorithms and SAGA. Can you do the same for the algorithm "Merge shapefiles to ...
1
vote
2answers
192 views

Qgis making a backgound map for topolines on Garmin

Hi I am a new user of QGIS, I would like to make a Background map with Topolines in gmap or img format. So I started off with Opendem shape files. I have sucessfully combined the tiles I want into one ...
1
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1answer
162 views

How to programmatically export a composition as image?

QGIS Print Composer has tool "Save As Image" and I found appropriate function in QGIS source code exportCompositionAsImage. Is it possible to get access to existing Print Composer from Python console ...
0
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2answers
2k views

how to generate a NDVI in QGIS [closed]

i have tried using raster calculator to generate NDVI and tried searching for but couldn't find it. is there any other way to extract NDVI and what are the procedures to generate NDVI in QGIS.
3
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5answers
388 views

How to place labels under a vector layer?

I want to place the labeling under a layer. In QGIS 2.2 apparently the label appears automatically at the top. Can someone help me. (see attachment) example:
3
votes
0answers
77 views

How to find the minimum number of inspection points?

I am working on a pipeline inspection project and there is a high liklihood that some inspection tool deployment/retrival station will need to be installed on the pipe network. the problem is ...
1
vote
2answers
184 views

Using the Rule-based style to calculate each grid cell from overlaps

I am using the Rule-based styling properties (QGIS 2.2) to determine the colour of grid cells for a merged shapefile. Each grid cell defined by its ID may be overlapped by several layers as defined by ...
1
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0answers
66 views

Command-line tool for writing a print-composer to file?

I'm looking for a command-line tool, to write a previously generated print-composer to an image-file. The following resources I already saw: Related questions (1, 2) A gist Nevertheless, all them ...
0
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2answers
503 views

Any clue how to read a .style (ArcGIS) file in Python, for converting into another platform-specific format? [duplicate]

The problem I am face with is that I have all my data as shapefiles but my organization works with only 1 ArcGIS license. Migrating to QGIS to prominent amount of work, I need to convert my ArcGIS ...
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0answers
57 views

Scale keeps changing in QGIS composer?

Every time I pan the map content in the QGIS composer window the scale changes. Is there a way to make it stick at specific scale?
2
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2answers
87 views

qgis raster style 'no data value' checkbox is ignored - what's a good workaround?

See bug report filed here: http://hub.qgis.org/issues/10236 Note the initial bug report got 'fixed' but that fix introduced this new error, so the issue was reopened a few days ago. Anyway, it ...
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1answer
44 views

How to remove ghost layer in Qgis?

I added a delimited text layer to a Qgis 2.0 project, working in Windows, but it got added wrong: It didn't appear in the list of layers on the left panel, nor did it show in the map canvas. However, ...