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2
votes
0answers
16 views

Georeferencing multiple images (100 or more) of same region in QGIS?

I'm trying to georeference multiple satellite images of the same region over the course of a few years and get a separate output for each georeferenced image (a .tif file). How can I achieve this in ...
2
votes
0answers
20 views

How to symbolize raster with field values in QGIS or GRASS GIS?

I have a raster with ten field values. In ArcGIS I can open and select one of the field values for symbology and it show me the values from that field. How can I handle this in QGIS? I share a ...
1
vote
1answer
17 views

Need basemap with just state outlines

I am very new to QGIS. I am working from work so there is extra security which is why I think I have problems accessing OpenLayers plugins. The only one that seems to load is Google Maps. Google maps ...
1
vote
0answers
26 views

How can I handle an Excel spreadsheet in QGIS (2.14)

There seem to now be many methods for working with an Excel spreadsheet in QGIS. Some allow read-only, and some require one Excel format or another. What are the main different methods for working ...
1
vote
1answer
18 views

Creating new layer out of features selected using expression, in QGIS?

I have lots of points representing buildings, scattered on top of polygons representing output areas of a city. I'd like to select only those points that have a certain descriptor in their database, ...
1
vote
2answers
19 views

Preserving Projection on SAGA-produced Rasters

I perform a fair amount of hydrological processing in QGIS and rely on SAGA's Topographical Wetness Index and slope-derived functions. In order to use them, SAGA demands that input rasters are warped ...
1
vote
0answers
12 views

ECW support on QGIS version 2.14.4-Essen (Ubuntu 14.04) [on hold]

someone know how to abilitate ECW support on QGIS version 2.14.4-Essen (Ubuntu 14.04)?
1
vote
1answer
33 views

How to copy attribute table definition to a SHP to another?

I have a SHP with 3D vectors and in the other hand, a SHP with attribute table definition. I need one SHP with the 3D vectors and the attribute table definition. I tried to copy/paste the 3D vectors ...
0
votes
0answers
17 views

qgis/remote sensing/OTB : needs & expectations? [on hold]

As part of a mission project, I talk currently with a significant contributor to the development of qgis. We wonder about needs & expectations of the users and developers regarding remote sensing ...
2
votes
0answers
19 views

Dissolving shapefile but retaining original attribute fields in QGIS

How can I dissolve a polygon layer in QGIS based on a single attribute but keep all (or some) other attributes at the same time? This is how I want to retain fields: There are at least two fields I ...
1
vote
0answers
33 views

PyQGIS + selection

I would like to select some lines in the layer that match this condition : the attribut A have to be the same as the value of the "for" loop where the selection is realised. (After fixing that ...
2
votes
4answers
64 views

Downloading Scotland's national power grid from OpenStreetMap

I've been tasked with finding a complete dataset of Scotland's electricity grid network. This comprises a series of cables carrying 132 to 400 kV. I'm assuming that many of these cables are above ...
2
votes
3answers
80 views

Prevent export to shapefile from postgis table in QGIS

I have created a centralized database using postgreSQL and created multiple users assigned with different roles i.e. SELECT, UPDATE, MODIFY and DELETE etc. Example: CREATE USER hasan WITH ...
3
votes
1answer
31 views

Error using Grass v.clean

I am trying to clean topology of a TAB file in QGIS 2.14.4 and it returns an error message as below The weird thing is, I am able to execute this okay on my machine but not my colleague's. The other ...
-2
votes
0answers
17 views

QGIS crashes when a WMS/WMTS layer times out

How can I get QGIS to not completely crash when one WMS/WMTS layer is having problems communicating with the service. If the network is having difficulty, fine. This should not crash the entire ...
2
votes
1answer
22 views

Seeking documentation for qgis.utils module?

There is a PyQGIS module called utils that I can't find any documentation for. It seems to have some useful functions for loaded plugins. Within the Python console in QGIS you can run qgis.utils....
0
votes
1answer
25 views

Visualising DEM with threejs plugin?

I have DEM file for a small mountain created from TIN interpolation of points. The DEM looks correct on the flat QGIS working area. The moment I try to visualize a 3D of the DEM using threejs, I get ...
1
vote
0answers
16 views

Errors executing certain algorithms in QGIS Processing Toolbox?

When I execute certain algorithms in Proccesing Toolbox, for example "Convert polygon/line vertices to points" I get the following error: Algorithm Convert polygon/line vertices to points starting....
2
votes
1answer
31 views

PyQGIS refresh layer tree programmatically

When programmatically applying a subset string to a vector layer (here: ax_flurstueck with object count 34265) via l = iface.activeLayer() l.setSubsetString('gemarkungsnummer in ('2760','2765','...
0
votes
1answer
13 views

Density Slicing of MODIS Raster

I have some MODIS data processed with MRT tools. They are now in tiff format. Now, I have to complete Density slicing to identify water pixels from the image. The DN higher than 1985 is usually non-...
0
votes
1answer
18 views

Qgis2threejs error after changes in qgis-ltr-bin

I have installed QGIS 2.8.9 in C:\OSGeo4W folder and change qgis-ltr-bin.bat last line with start "QGIS" /B "%OSGEO4W_ROOT%"\bin\surveykshak.exe --configpath "%OSGEO4W_ROOT%"\qgisini%*. I changed ...
0
votes
0answers
33 views

Opening ESRI Personal Geodatabase (*.mdb) in Ubuntu QGIS? [on hold]

This question has multiple components. (1) The immediate problem: Cannot load the data from a file called landuse.mdb into QGIS. Ubuntu version: 14.04 LTS, 64-bit. Mostly vanilla install. QGIS ...
0
votes
0answers
12 views

Snapping a point Exactly On a Line in QGIS 2.8.6 [duplicate]

I have a layer with points (representing train stations) and another layer consisting of lines (representing rail roads). I would like to snap my train stations exactly on the rail roads and not in ...
1
vote
1answer
17 views

QGIS 2.14 hangs at “Starting up the GUI” and fetching plugin repositories

All of a sudden, QGIS 2.14.4 hangs on startup on Win7 for at least 2 min. Eventually it starts without error. Hardware is not the issue (Core i7, 8GB ram, etc.). I tried reinstalling with OS4Geo ...
1
vote
0answers
29 views

QGIS 2.14.4 How to get the legend of a Vector heatmap layer?

I'm new on QGIS and PyQGIS. I'm trying to create a plugin which aims to apply a style on a vector layer (generated from a csv file) and then save the map as a png file. The style I apply on the ...
0
votes
2answers
27 views

Calculate surface area of polygon within the lines of another polygon

I have two shapefiles, both polygons. 1) The first file represents the administrative boundaries of provinces. This file contains a lot of fields. [social, geographic, natural, morphological etc] 2) ...
1
vote
1answer
24 views

PyQGIS QgsVectorLayer.uniqueValues() override active object filtering

This code snippet gives me the unique values for a vector layers attribute called myfieldname l = iface.activeLayer() attrIndex = l.fieldNameIndex('myfieldname') uniValues = l.uniqueValues(attrIndex) ...
0
votes
0answers
19 views

Working on query builder in QGIS?

I installed QGIS 2.16.1 and i want to work with the data using query builder. It was active and when i click it nothing pops us and now it is just deactivate. Is it related to plugin or what ?
1
vote
2answers
28 views

Updating attribute field with random string value

I have a shape layer in qgis with blank attribute table. I want to fill attribute table with false data randomly. I successfully update the field with integer values using 'rand' expression. I am ...
1
vote
0answers
23 views

QGIS Snow Cover extent extract

I have a year worth of daily snow cover data in tif files. I want to merge them all into one (stack) and select a polygon from which I want to extract snow cover extent as in sqare miles and as % of ...
1
vote
0answers
23 views

Is it possible to build a route profile for a street with “real” heights considering tunnels and bridges?

Is it possible to build a exact route profile for a street with "real" heights considering tunnels and bridges in an easy way with free data? Of course it is possible to remove thy waypoint located on ...
1
vote
0answers
42 views

Resolving geometry errors in QGIS

I have a shapefile where the geometry is a mess, lots of gaps, slivers, and holes. I need to correct these geometry errors, but I am having trouble with the process. I have read the pages here, here ...
2
votes
1answer
29 views

Loading REST Service in QGIS?

How do I load this REST service in QGIS? https://tpwd.texas.gov/arcgis/rest/services/GIS/Ecosys1/MapServer The ArcGIS REST API Connector returns the error: [Errno 1] _ssl.c:504: error:14090086:SSL ...
0
votes
1answer
32 views

Missing qgis icon resources for symbology dialog

I'm trying to call QgsRendererV2PropertiesDialog from a standalone Qgis python script. It mostly works, except there's some "unknown error" messages related to SVG files when I trigger the dialog: ...
0
votes
0answers
19 views

Add attribute value from a Point layer to a Line layer in QGIS

I have extracted nodes from a line shapefile. On these nodes, I have extracted altitude values from a raster DEM using SAGA 'Add raster value to point'. I want now to make the inverse of the first ...
0
votes
0answers
26 views

Dasymetric mapping in QGIS?

I have the following shape layers: Rivers.shp NaturalArea.shp CountyBoundary.shp And I have a Census table showing the population count within the county. Now obviously nobody lives in a river or ...
1
vote
0answers
43 views

Why does QGIS 2.16 have longer load times than 2.8, especially working with tables?

I was previously running an LTR version of QGIS (2.8.9 I think). I installed 2.16 and found that opening tables takes a very long time. Deleting columns in tables now takes hours as opposed to seconds....
0
votes
1answer
26 views

qgis2web Plugin Broken?

After the qgis2web plugin was upgraded last week the popup window shows all fields in the attribute table when you click on a feature regardless of which ones were selected in the dropdowns when ...
0
votes
0answers
35 views

Shortest path between some points in QGIS

I'm using QGIS software to calculate shortest distance between 750 points (rental stations of the bike sharing of London) on OpenStreetMap. The lines should follow the streets of the map downstairs. ...
3
votes
0answers
47 views

Determining the first and last point that a polygon intersects

I have this... And I want to join those attributes to the polygon automatically: Because I'll have to replicate this on tones of those polygons. If this works I would like to know if it still ...
1
vote
0answers
14 views

Troubleshoot with “Split selected features with selected line from another layer”

I am trying to use the "Split selected features with selected line from another layer" tool from the plugin Digitizing Tools in QGIS. Sometimes, this tool works with my shapefiles but sometimes it ...
0
votes
1answer
30 views

Rendering polygons with Qgis2threejs?

I have a polygon shapefile cotegorised according to a specific field. I want to present that 3D with the help of Qgis2three.js (sth like that). I have installed the plugin and have chosen the polygon ...
0
votes
0answers
4 views

Creating a COM object from QgsMapCanvas

I want to embed a QgsMapCanvas object to a Windows Form. I did some digging but couldn't find much about if anyone has done it before. Is this theoratically possible and/or practical?
-1
votes
0answers
20 views

QGIS Legend in print composer is corrupted

The legend in the print composer seems to be corrupted. It only shows a few items and when generated; stretches to a massive size and cannot be made smaller. This is a frustrating problem and I just ...
0
votes
0answers
22 views

How to add WMS Layer in custom projection to Qgis?

I published layer from ms-sql server on Geoserver. In sql table i have srid=60900. On Geoserver srs=60900. In Layers Previews layer looks nice. Now i tried show it in Qgis. I add projection and call ...
5
votes
1answer
67 views

Stop Qgis layer from refreshing every time I pan

I've got a layer in a QGIS project which source is a PostGIS view. It's a quite complex view and needs like 20 seconds to load (it makes several spatial analysis). My problem is that the QGIS project ...
0
votes
0answers
15 views

laszip batch process in qgis extension lastool

i am using qgis 2.16 in that lastool plugin contains laszip option. please tell how to run batch process in laszip. ill not able to add multiple files at a time in batch process.result came only for ...
0
votes
1answer
28 views

QGIS Topological editing error - the new polygon overwrite the existing one after saving layer edits

I'd like to digitalizing a map and when I draw a new polygon which overlaps an existing one, at first it merges the boundaries correctly, but after i'm saving the layer edits, the new boundaries ...
0
votes
0answers
23 views

QGIS “error: Grid file could not be opened” when filling sinks

When trying to run "Fill sinks" for SRTM30 data, there is a error and the log shows there was an "error:Grid file could not be opened". For the parameters: DEM: SRTM30 data; Sink route: [Not selected]...
0
votes
0answers
26 views

coordinate system are same unit also meters, but maps are not overlap [duplicate]

coordinate system are same unit also meters, but maps are not overlap WGS_1984_UTM_Zone_44N Projection: Transverse_Mercator False_Easting: 500000.000000 False_Northing: 0.000000 Central_Meridian: 81....