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

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6 views

mmqgis plugin not showing up in plugin dropdown menu

I have installed the plugin from the plugin dialog box, but I am unable to figure out exactly how to run the plugin.
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2answers
35 views

CRS for submission to Minnesota DOT

Does anyone have experience using QGIS to submit shape files to the Minnesota DOT (MNDOT)? I am using EPSG:26915 but got rejected due to an error in the CRS. MNDOT Specs call for "UTM coordinates, ...
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1answer
20 views

line intersection point in a street layer in postgis 1.4

I have a street layer downloaded from osm. I need to calculated intersection point as we do in qgis from vector menu -> Analysis tool -> Line intersections. I am new to postgis/postgres. any how i ...
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11 views

*Value relation* widget in QGIS

I cannot understand what the Value Relation widget of the Fields menu in QGIS actually does. For example: I have a point layer with some columns (ID, value1...) and a table (so just a dbf file) with ...
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1answer
30 views

How to merge two different dem rasters to a one dem raster? [on hold]

I have two dem raster files (.tif and .asc). The other one (.asc file) is bathymetry data with zero values at land and from -0.08 to -44.5 in the water areas. The other is topography dem raster (.tif ...
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9 views

Can QGIS open a SDF file created by HEC RAS?

I used the "export GIS data" option in HEC RAS and got a SDF file. Is it possible to open it in QGIS?
2
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1answer
28 views

How to install LAS tools in Processing for QGIS 2.4?

Does anyone know were the processing menu moved in QGIS 2.4? Specifically I am trying to install the Lastools box for QGIS following these instructions. ...
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0answers
39 views

Creating a new shapefile based on an existing problematic shapefile

I have a large floodplain shapefile and would like to create a new shapefile based on coverage. I'm having major problems with the original (intersections and other errors) which I've been unable to ...
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0answers
12 views

QGIS DEM Output cell size does not match DEM input cell size

As my first post I offer a humble apology if this is such a basic question as to make any of you cringe. I feel like I have exhausted my search skills and read through the QGIS documentation ...
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3answers
167 views

How can I work with very large shapefiles (~1 GB) in QGIS?

I'm performing some basic spatial analyses on a large database of traffic injuries in California between 2003 - 2011. Because the dataset is large (nearly 1 GB of points), I'd like to first cut it ...
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0answers
22 views

Will QGIS fulfill my requirements? moveable, rotatable, draggable, complex, interactive icons

I'm trying to compile a list of mapping software that will fit my requirements for a desktop application I want to build. I'm trying to build something similar to MissionPlanner: ...
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0answers
19 views

Is there a Targer-like tool for QGis?

I'm trying to make subsurface drillhole and I heard that Target (an AutoCad tool) can help me with this task but the issue is that I work with QGis.
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0answers
14 views

QGIS distance from points to nearest line

How can I get the distances from each point at a shapefile to the nearest line from another? I've tried to follow the directions from Measuring the distance between lines and points in QGIS and ...
2
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2answers
26 views

QGIS Raster Calculator: Need values to be set to 0 instead of no data

I have a landcover map with different values for the landuse options e.g. 190 for commercially used areas. Now I want to extract only these areas using the Raster Calculator with the expression ...
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0answers
19 views

Tagging polygons within larger polygons (spatial join)

another QGIS newbie here. I have a number of smaller polygons which perfectly aggregate to a larger polygon. I want to "tag" the smaller polygons with the ID of the larger polygon they make up. ...
2
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1answer
44 views

In which way is height information stored in a DEM?

I'm struggling with different DEM data, because I don't know how to convert the height information in meters. When I load ASTER and SRTM tifs in QGIS, it shows me the spectrum of the grayband (0 to ...
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1answer
25 views

How to batch-process attribute tables in QGIS (or GRASS)?

I'm using GRASS 6.4.3 in Linuxmint 16. I have a bash script for GRASS which I use to process almost 300 raster files. The script first imports some raster files (r.in.gdal), then does some ...
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1answer
28 views

Is there a way to define the relative position of items in print composer?

Is there any chance to make the items in print composer relative to the margins. Let's say for example the legend. I normally align it to the corner on the right bottom where the legend is 10 px away ...
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0answers
41 views

How to create a rainfall raster from rainfall contours?

I downloaded a free rainfall data from the Philippine GIS Data Clearinghouse (PhilGIS) which are vector lines. How can I extract the data points from this? I want to extract it because i will be ...
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0answers
27 views

Converting DEM data to height information in meters using QGIS?

I'm relatively new with QGIS and currently I'm working with ASTER and SRTM DEMs. The goal is to create vector heightcontours with labeling in meter. Can you tell me how I can convert the grayband ...
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0answers
20 views

How to sort a column in attribute table programmatically

Is there any way to sort ( alphabetically ) a column in the attribute table programmatically (without clicking on the column header) in QGIS ?
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0answers
27 views

Modifying properties of Attributes Table in QGIS?

In my QGIS project I'm using vector layers that require a lot of data inputting/editing. The problem is that some of the data I'm inputting varies greatly in matter of length and structure (various ...
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0answers
15 views

Creating a marker proportionally offset along a line in QGIS 2.4 when re-projecting

One of the nice new features in QGIS 2.4 is to be able to offset markers (e.g. arrow heads) along a line as part of the styling. I am trying to display a dataset of simple lines (not polylines) with ...
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0answers
10 views

r.stream.* commands do not work in qgis environment

I have been working for a while with some grass commands in QGIS environment (r.watershed, r.terraflow, r.thin, r.to.vect etc) with out any problem. I haven't been able to get any results at all from ...
3
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1answer
28 views

Wrong scale when importing dxf into QGIS

Has anyone had the problem that the scale of the shp layer converted originally from a .dxf file turns out to be wrong? (for example I draw a line of 10 meters long in AutoCAD and imported it in QGIS, ...
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0answers
29 views

from shape files to a database

I've previously converted simple shape files to WKT so that I can store them in RDMS that has spatial capabilities. I'm a new user to QGIS, which I'm using to browse a shape file. But now I have a ...
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0answers
10 views

Raster Analysis Grid (Interpolation) Crashes

Upon clicking on "Grid (Interpolation)" QGIS crashes. I running QGIS 2.2.0-Valmiera on a Mac with OS X 10.9.4 Thank you for any trouble shooting guidance
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0answers
31 views

Polygonize Missing Polygons

Polygonize is not capturing all of the pixels in an image that has been converted to 0s & 1s. The pics below show -original geotif -geotif recalculated to 0s & 1s -polygonize output As the ...
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22 views

Are there reference manual pages anywhere for QGIS built-in “buffer” and plugin “points2one”?

Perhaps I am missing some quick pop-up help mechanism, but as a relative newcomer to QGIS (having cut my teeth on ArcGIS 10.1), I am struggling to find reference manuals (i.e. explanations of all ...
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1answer
26 views

Loading GRASS gives error installing QGIS Chugiak on Windows 8.1?

I am experiencing a problem installing QGIS 2.4 Chugiak on Windows 8.1, resulting in a error loading Grass. This may be a problem only affecting certain installations, I'm not sure. I am a noob on ...
2
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1answer
47 views

data source for worldwide cross-sections of topographic and bathymetric for woodworking art project?

i am a decent r programmer and statistician, i am able to work with data sets pretty well. i am less familiar with GIS tools, but if given a shapefile i can certainly plot political borders and ...
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1answer
45 views

Accuracy issues between data in QGIS and Google Earth

Wondering if anyone can answer this question. I have a kml in Google Earth. When I import it to QGIS, and then import the Google Earth images they are in slightly different places. I used a QGIS ...
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15 views

QGIS error when add WFS

I'm running QGIS 2.4.0-Chugiak on win7 64bit and am getting the following error while trying to add a wfs layer (using the simple Add WFS layer command): The layer ...
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1answer
21 views

Couldn't load SIP module (QGIS doesn't load Python)

I recently installed QGIS 2.4, but Python does not load. I am running on a Windows 64 bit machine. I receive the error message "Couldn't load SIP module Python support will be disabled". Traceback ...
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1answer
44 views

Qgis - Labels automatically resize to fit within the polygon

The question of my problem is simple, I want to make labels automatically reduce to fit within the polignos. Type the biggest size is 12 and goat decrease the size to be restricted to the limits of ...
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0answers
10 views

Is it possible to leave a field null when using the calendar widget in QGIS?

I'm creating and editing data with QGIS, the data is stored in a Spatialite database but I've run into this issue with shapefiles as well. I have a field I'm storing dates in and I want to use QGIS' ...
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0answers
14 views

QGIS strongly offsetted symbols for categorized layers not visible on layer list (layer panel)

I am constructing a symbology for telecom analysis, which so far is mainly point and line features. So far it is working very well except that I have to offset the symbols to be able to avoid ...
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0answers
9 views

QGIS SimpleSymbolRenderer label for Symbol in Legend

Is there an ability to set a label for the symbol (in QgsSingleSymbolRendererV2) which is showing in the legend?
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0answers
27 views

Is it possible to rotate the geographic projection in QGIS?

I'm trying to create a Qgis plugin that can rotate a raster layer in the canvas so that the north is pointing at another direction. Unlike the thread below, I'm open to defining a custom projection. ...
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0answers
21 views

Positioning and tracing polygons over an image

On QGIS 2.0 - I want to add an image (TIFF or whatever) then resize and correctly position it over a satellite image (openlayersplugin). Then, the task is to create a new shape file layer and draw ...
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2answers
59 views

Is there a way to “zoom to feature” in QGIS?

I am the GIS Director of a city public works. I have a shapefile that I created of points on each structure and address in the city. We have been working in ArcMap Desktop for 6 or 7 years and depend ...
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1answer
35 views

What is the inverse of QgsGeometry.asGeometryCollection() in qgis python?

What is the inverse operation of QgsGeometry.asGeometryCollection() as documented here: http://qgis.org/api/classQgsGeometry.html#a7cb1cbf8cfa441456067a66ad3a25a94 I'd like to do something like: ...
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0answers
28 views

QGIS 2.4.0 Chugiak “reduced” real-type numbers. Precision problem? Bug?

I have a SHP point file created from CSV with QGIS 2.4.0 Chugiak. It contains some data on noise in a certain point. When I import from CSV, it seems to be fine, but when I export to SHP and open the ...
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0answers
16 views

How to move a layer in QGIS Toc above an existing group?

If in QGIS TOC a group already exists and I add a new layer via QgsVectorLayer* lyr= mQGisIface->addVectorLayer(uri->uri(),Title, myProviderName); the new layer will be inserted within the ...
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0answers
21 views

Creating random points [on hold]

I think I am just missing something simple but I am unable to get my random points to occur within my polygon boundary area using the random points tool in QGIS 2.4.0. I end up with my points up in ...
1
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1answer
31 views

Interpolation of xyz data

Data has been given to us in a HUGE .xyz file, which has been split into many component CSV files. When I upload the CSV file, then create the shape file by "save as", all is fine. When I go to ...
3
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1answer
169 views

Extract one GPS fix per day from data?

I am in the fortunate position of having 2 years worth of animal movement data. With such a large amount of data I would like to extract only one fix per day to make it easier to work with. Data = 14 ...
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1answer
20 views

Set a Required Field in QGIS Edit Form

Is it possible to make a field required in a QGIS Edit Form?
2
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1answer
19 views

QGIS, CRS's and metric measurements of distance matrix and nearest neighbour

I have thousands of points on a multiple layers and I need to get the distances between each point and every other point within a layer (so i can get min, max, mean and median distances) and the ...
2
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1answer
35 views

How to add labeling to a polygon layer?

I'm trying to add labeling to a polygons vector layer called "myVectorLayer". It does not give me an error but the labeling does not appear. palyr = QgsPalLayerSettings() ...