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

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0answers
15 views

Render Vector & Save as Raster

I am working with ENC files from noaa, specifically S57 format or ".000" to be as specific as possible. I am trying to render a layer or even the entire thing in a window but have had no luck. ...
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8 views

How to get the name of the layer on a map composer with a single layer?

I tried layer_property( 'layer', 'title') I would like to return the current layer from the map instead of 'layer'. (or list of the layers on the map?) Doesn't seems to works with layer_id or ...
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0answers
6 views

Activating LAStools - 'wrong value for parameter “Msys folder”'

Whenever I try to activate LAStools, I get the following error, despite setting the path as /Users/grant/LAStools/ - which is its actual location: Wrong value for parameter "Msys folder": ...
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1answer
24 views

Converting Shapefiles

Can anybody help me on how to convert shape files into .asc files? I want to convert layers from shape files into this format but I don't know how to go about it in qgis.
2
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0answers
19 views

How to convert from a local coordinate system to UTM (and vice versa) using mathematical expression

I have two coordinate systems- UTM Zone 23S and a local one with the following conversion from UTM to Local: EASTING: SQRT( (UTM_EAST-296787.355)^2 +UTM_NORTH-8095123.271)^2) ...
0
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1answer
25 views

Is there a plugin or another way to quicky edit the attribute features in QGIS?

I want to edit the field "name" of several roads in QGIS 2.14. How to do it very quickly? Currently I select with "Identity feature" tool that open Form Feature Attribute, then with the mouse I ...
3
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1answer
49 views

QGIS: Legend with more columns in one row

I have two layers (water_supply_design, water_supply_condition). I'd like to create new map with Map Composer in QGIS. In this map, I'd like to have a legend with one row and two columns (Water ...
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2answers
17 views

How do I use geometry object in processing.runalg()

I am trying to clip a polygon (large road network) with every row in another polygon (district polygon) using PYQGIS. layer_adm_level = QgsVectorLayer(base_path + adm_level + ...
1
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0answers
17 views

qgis web client zoom and center maps

I have a problem with " qgis web client" I can not find the option setting center of maps and change the zoom ?? I was looking at globaloptions but I managed to ; / Regards
1
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0answers
17 views

How to draw weighted voronoi polygons ( thiessen) from points in Qgis?

I have a shapefile of polygons which have an amount of population, I need to divide each of these polygons into small ones with nearly equal population. So I thought attributing points on each area ...
1
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0answers
18 views

Why is the QGIS 2.10 raster clip function not working correctly?

I am using QGIS 2.10 and everything seems to work just fine so far, except for the raster clipping function (Raster>Extraction>Clipper). I'm using a vector poligon as a mask layer, but after launching ...
4
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0answers
29 views

How write python code with QList class

I need write a interpolation script for QGIS. I want use TINInterpolation method from Interpolation plugin. I found class in API documentation but I don't know how write QList object with attributes ...
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0answers
8 views

Automating the Road Graph “shortest path” plugin in QGIS to batch compute routes

Is anyone aware of how to automate the Road Graph "Shortest Path" plugin in QGIS, calculating multiple routes from multiple origins to multiple destinations, using two point files and road network, ...
1
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0answers
35 views

Measuring Volumes using DEMs

I've done quite a bit of research here and elsewhere and am still having trouble coming up with a solution for measuring volumes using a DEM derived from high-resolution (1 m) stereo satellite ...
5
votes
1answer
43 views

How to create points along a line according to attribute data in QGIS?

I would like to create equidistant points along lines in QGIS, but each of my lines have an attribute of how many points should be on them in a column called "piece" and these values are different in ...
2
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0answers
14 views

rename table/feature class in filegdb using ogr or qgis

According to the OGR SQL docs, it doesn't appear that it is possible to use and ALTER statement to rename an existing table (featureclass) inside of a file geodatabase. RENAME statements can be run on ...
4
votes
1answer
38 views

Why QGIS WFS doesn't update PostGIS line and polygon layers?

I installed PostgreSQL and PostGIS and created PostGIS layers in GeoServer. But when i want to change geometry in QGIS via WFS it drops an error: ": Error performing insert: java.lang.String cannot ...
3
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0answers
23 views

How to generate static heat maps server side?

I've been searching a way to generate server side static maps using Python (or any other languages, doesn't matter) I can create the maps I want with Qgis (And they look really great) but I don't ...
3
votes
1answer
44 views

Importing large .asc files into QGIS

I've been given two .asc files containing a 1m raster data from a LiDAR survey. I only have access to QGIS.2.14.1 (which I'am using for the 1st time only having previous experience with ArcGIS) and I ...
0
votes
1answer
21 views

Comparing areas of overlapping shapes in QGIS

Given SHP files for a country's Districts in Year1 and Year2, how to output a table whose rows state the percentage composition of each Year2 District in terms of portions of Year1 Districts
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0answers
13 views

How to show map direction of a DEM in Q gis [on hold]

How to show map direction of a DEM in QGIS and how to show direction of the MAP?
0
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1answer
10 views

R.patch creating enormous file size

I'm using r.patch (within QGIS, GRASS 7) to patch two Float32 rasters both of which have a respective filesize of under 200MB. When I save the memory layer raster created by the r.patch function, the ...
4
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1answer
24 views

Positioning of graticule labels in QGIS 2.14.1

I have a map grid (line, shp) that was created with MMQGIS. The X and Y coordinates of the lines are stored in the the attribute table, which makes labelling the lines an easy process. My problem is ...
2
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0answers
37 views

QGIS managing relationships

Coming from an ESRI background I'm used to ESRI geodatabases (.mdb or .gdb). In those databases, I could create feature classes, tables and relationships between them. Every time I loaded a feature ...
2
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0answers
30 views

How to digitize 3D geospatial data using FOSS applications

I need to digitize soil horizon data from photos to be later used in a 3-dimensional GIS workflow. For each photo I have DGPS coordinates of the top left and right corner and the depth of the ...
3
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1answer
47 views

Application of preset properties QGIS layer to another imported shp

In QGIS I import the same shp files during days (continuously fieldwork). For processing in QGIS I set the properties of layer (imported shp)- Style, Labels, Actions, Display. In these days I have to ...
2
votes
3answers
48 views

Merging tif images into a single GeoTiff with QGIS

For this example, I have 3 tif images that are tiles. They fit together to form a single image. I load the 3 images into QGIS and it merges them directly and I see my completed image. The problem ...
1
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0answers
19 views

QGIS “buffer” considering grades

I have to develop an article entitled as "GIS IN ASSESSMENT OF BUS TRANSIT SYSTEM ACCESSIBILITY CONSIDERING GRADES". I'm still at an early stage of development of the research project, but I have ...
1
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0answers
12 views

PyQGIS: intersection of one node layer with two polygon layers

I´m new with the use of PyQGIS and I´m working in a problem applied to a water supply systems modelling, where I need to distribute the water demand in about 5000 nodes (network junctions). I´m ...
2
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0answers
12 views

Issue loading PostGIS out-db rasters (either in QGIS or MapServer)

I'm playing with a few different options of storing raster data via PostGIS to visualize (eventually in a web app). The out-db or out-of-database storage seems the best option, but I can't seem to ...
1
vote
1answer
17 views

qgis feature classification of filegdb datasource bug?

When I am trying to create a symbol classification from a filegdb datasource in qgis the list of unique attribute values is not being populated when I hit the 'Classify' button. It loads a single ...
3
votes
1answer
21 views

How to keep live update coming from a WMS

I'm using a WMS that contain weather radars that is update every 10 min. I would like to know how to keep the map updating every 10min. I tried: from PyQt4.QtCore import * timer = QTimer() ...
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0answers
8 views

Why does QGIS try to create spatial tables when loading into MSSQL Server?

When trying to load a layer from the QGIS layers panel or browsers panel, errors pop up that either the 'spatial_ref_sys' table or 'geometry_columns' table exists: If these tables exist already, ...
1
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0answers
16 views

Error with SAGA's Topgraphic Correction

I am using QGIS 2.14.2, trying to perform a supervised classification on a rapideye image with the SCP plugin. To improve my classification im trying to work with the SAGA's topographic correction. ...
1
vote
1answer
19 views

Using Title Case on Everything Except Last 2 Characters

I have addresses in my attribute table that I converted to title case from upper case. Example: 123 FAKEVILLE ST NW to 123 Fakeville St Nw How can I make it so that the last 2 characters in all ...
2
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0answers
28 views

Unwanted display of 180 meridian in map [duplicate]

When I use the WGS 84 CRS the Chukotka peninsula east of the 180 meridian is shown on the left of the map. If I project (on-the-fly) the map using a Lambert Azimuth projection, the Chukotka peninsula ...
1
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0answers
21 views

Raster Precision QGIS

I am using r.patch extension in QGIS to join a number of LiDAR tiles, some of which overlap hence i am carrying out this task before utilising in a hydraulic model. R.Patch works fine, however the ...
1
vote
0answers
23 views

Help with Python shapefile Union Program

First I am a Python noob... I have searched the database for this answer, found a few that might be the answer, just way over my head (I am signed up for a intro python class this month, to help ...
2
votes
0answers
17 views

MODIS Imagery Orthorectification (Open Source)

I am looking for an open source free software/tool for orthorectification/Geometric terrain correction of MODIS imagery. I have looked at ESA (European Space Agency) SNAP but this sensor type is not ...
2
votes
1answer
37 views

QGIS: How to modify the appearence of selected attributes [duplicate]

I am using QGIS version 2.14.1 (Essen). When I open the attributes table of a layer, I select some data which is then highlighted in yellow on the map. I was wondering if it is possible to change the ...
1
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0answers
38 views

Update Join Attributes by Location

I have a shapefile with points, and a shapefile with polygons. I want to sum the attribute value of all points that are contained in a polygon, and I'd like to do this for each polygon in my dataset. ...
1
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0answers
34 views

How to incorporate QGIS custom widgets into plugin? [duplicate]

Developing a plugin with Qt Designer for QGIS 2.14.1-Essen on Windows 7 and having trouble inserting the QgsCollapsibleGroupBox widget. I receive the following error: ImportError: No module named ...
1
vote
1answer
19 views

QuickMapServices It is not for ubuntu?

I'm new using QGis. I read somewhere that QMS was better and more stable than the OpenLayers complement to use Google Maps. My problem is that it does not appear when I search with the plugins ...
-1
votes
0answers
28 views

Calculating total area overlapping raster DEM color interval whose boundaries are confined by another vector? [duplicate]

Example: I tried running raster calculator on intersections then zonal statistics checking "count" and "sum" but I get a huge table of 8000+ rows and two columns, however each cell usually have a ...
3
votes
1answer
30 views

Convert fields of points into separate polygons based on their outlines

I have several fields of points that look like so: They are actually thousands of points that appear as polygons because they're so close to one another. They're research points 720 feet from one ...
4
votes
0answers
27 views

QGIS Renders Buffer Polygons from ArcGIS Feature Class Differently

I have a polygon feature class stored in an ArcGIS geodatabase. All of the shapes are buffers of a point layer created using the editor menu's 'Buffer' command. In ArcMap 10.3.1 the data looks like ...
4
votes
2answers
51 views

Issue with QGIS 2.10.1 Clip and Intersect Tools

Having an issue in QGIS 2.10 -- clip and intersect don't seem to be working correctly. I am trying to show zipcode by a legislative district in Florida. When I clip the zipcode shapefile by the ...
1
vote
1answer
50 views

Styling a heat map based on point attribute, not density

I have a point dataset generated from getting the centroid points from a fishnet/polygon grid. I combined these points using a spatial join to give them an attribute of 'pressure' which is an integer ...
2
votes
0answers
23 views

QGIS Broken Link to files on a server

My colleagues and I are using different versions of QGIS (2.8.2, 2.86 & 2.14) on windows 8.1 and Windows 10. When we open existing projects we get a "Handle Bad Layers" box coming up. We have ...
2
votes
2answers
33 views

QGIS Segmentation fault when manipulating QgsGeometry

So I am running QGIS 2.8.1 on Ubuntu 14.04. This following problem is happening in my script, but also occurs directly in the QGIS python console: lay = iface.activeLayer() lay.featureCount() 1L ...