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2
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0answers
68 views

How to change values in a raster file at particular positions?

I have a collection of coordinates which comes from a QGSGeometry object. The shape is a polygon. example: qgsGeometry [[(75.2172,17.6566), (75.8499,17.9613), (75.5218,17.2113), (75.2172,17.4574), ...
1
vote
1answer
193 views

Using r.mapcalculator in Python console?

I'm trying to use the r.mapcalculator algorithim in a python script, but I'm having problems in using the r.mapcalculator to tranform a raster layer with float values into integers. Using the ...
2
votes
0answers
107 views

How to customize the visibility of buttons in QGIS?

The built-in toolbar named "Composer" has an icon "Duplicate Composer". I wish to toggle the visibility of this button in the toolbar. How do I achieve this using pyqgis?
2
votes
2answers
1k views

Vector -> Geometry Tools -> Extract Nodes equivalent in PyQGIS API

My question is fairly straight-forward. Would anyone know the PyQGIS equivalent of the Extract Nodes tool in QGIS? I don't seem to find it in the API documentation. If you do, kindly share the ...
1
vote
1answer
237 views

QGIS how to 'compare' points (latitude/longitude) w/address data (zip) to a zipcode boundaries shapefile

Hello my fellow GIS brethren, I am a geography major (gis) alumni who can't remember what he learned in college! It's been so long since I dealt with geospatial data and I can't remember the best ...
2
votes
2answers
208 views

How to fix the broken MGRS Tools plugin?

Here the case: i have a plugin installed in .qgis2/python/plugins that remains broken and i cant make it work. I've found it here https://github.com/volaya/mgrs-tools. If any of you know the way to ...
1
vote
3answers
194 views

Appending data in PostGIS database with QGIS?

I 'm running postgis with qgis 2.6. I created a database and tables that i need to update with new datas provided with shapes. I cannot find how to insert them in table. All attributes both shapes and ...
1
vote
1answer
59 views

georeferenced raster coordinates

In QGIS 1.8 I have two rasters derived from the same multi-band tif image (1) ndvi - each pixel contains NDVI values. Using /Plugin/Analysis Point Sampling tool a new vector layer is created and the ...
6
votes
2answers
1k views

How do I view GTFS data in QGIS?

I would like to use QGIS to create my map. One data feed is the gtfs regarding to bus routes. I can view it on Google Earth (although laggy), but when I tried to import the .kml into QGIS, it just ran ...
1
vote
1answer
75 views

How to sum up values of neighbouring rasters? [duplicate]

I have a raster (25X25 meter) and I will make a new raster where each cell get the value of the sum of all the raster cells in a radius of 500m. I use QGIS. What is the best option to do this?
1
vote
0answers
130 views

QGIS Mac OSX version cannot batch write output files after rasterization

Happy new year everyone, I have been trying to batch rasterize a series of .shp files using QGIS for Mac OS X, and keep coming up against a strange problem. I am using the QGIS 2.6.1 user interface, ...
1
vote
1answer
34 views

QGIS explode line function fails with OSM file

I am exporting a small extract from OSM. I load the lines(layer 1) into QGIS and apply the function Explode lines. I get the error: Algorithm Explode lines starting... __len__() should return >= 0 ...
2
votes
1answer
5k views

Opening Esri Personal Geodatabase (*.mdb) using QGIS?

Is it possible to open an Esri Personal Geodatabase (*.mdb; ArcGIS 10.2) in QGIS 2.6? Previous versions were right.
6
votes
2answers
2k views

How can I access `processing` with Python?

I want to access the explode lines function in Python outside of QGIS from a standalone script. What module do I have to load in order to use it? How can I access processing? from qgis.core import * ...
7
votes
1answer
424 views

Label placement on rotated map in QGIS

I'm a newbie to GIS and QGIS (please be nice to me). I'm working on a map for a garden/arboretum catalogue using QGIS 2.6.1. The arboretum has been surveyed using GPS, and the specimen trees and ...
2
votes
2answers
417 views

How to extract elevation values at line start and end points from a DEM?

I am new to the whole gis-experience and need your help working with QGIS. I have: DEM raster with heights (3d) line-shapefile which contains the rivers (2d) I need: heights for "start" and "end" ...
4
votes
1answer
708 views

How to find Chainage of points using QGIS

I have two types of Road shape files. Road (Polyline) and important points (waypoints) along the road. Both of these shape files are prepared using GPS. I want to find the chainage of the points. Is ...
2
votes
0answers
39 views

What should i do if the Repository tab “Status” was indicating “unavailable”.? (using proxy server)

In the plug in Repository tab. The "Status" was indicating "unavailable". I tried "hawkens" suggestion about the HTTPproxy thing but it didn't work (the network that I am using is a proxy server). ...
0
votes
2answers
388 views

changing pixel values using raster calculator Qgis

How could I convert a value of 32767 to a 0 using raster calculator in QGIS?
1
vote
2answers
153 views

How do I get UTM projected areas from a shape file created in QGIS?

I create a polygon (or point or line) .shp file in QGIS and it is automatically saved as WGS (as I understand, correct me if I'm wrong). That is fine by me despite being a bit inconvenient. Then I ...
1
vote
0answers
91 views

How do I step into the C++ functions from an external Python app I'm debugging?

I just wanted to see how to step into the C++ class QgsVectorLayer()'s methods from the python call to QgsVectorLayer(self.uri.uri(),'foo','postgres'). I'm trying to debug and it trying to step into ...
3
votes
1answer
172 views

How do I make curved labels for polygons in QGIS 2.6.1?

I have been able to find answers on how to do this in older versions of QGIS, but can't seem to come across anything that deals with the latest installment. I need a way to make labels curve to ...
3
votes
0answers
304 views

SAGA is not working within sextante (QGIS processing installed in Ubuntu)

Recently i decided to start working in Ubuntu (version 14.04). My first step was to add the ubuntugis-unestable repository, and then proceed to install SAGA, GRASS, OTB, QGIS and the bindings between ...
2
votes
1answer
434 views

How to extract percentage of land cover from a raster according to multiple shapefiles?

I have a raster map that represents land cover of a region, and different shapefiles (total 120) in the same region. I want to know the percentage of every land cover for each shapefile. For example, ...
0
votes
2answers
2k views

Import Aerial Images from Google into QGIS?

QGIS 2.6.1, Windows 7 I am looking to import an image from Google Earth into an existing QGIS project. Is it possible to download geo-referenced images from google maps (or google earth) and import ...
5
votes
1answer
2k views

How to compute Walking and Cycling Isochrone maps using QGIS & pgRouting?

Just installed QGIS as I believe I should be able to produce walking and cycling isochrones from a specified point. I have done this pretty easily before using ArcMap, however, I am really struggling ...
2
votes
1answer
214 views

Revert qgis 2.6 installation to qgis 2.4 through OSGeo4W Advanced installer

It is possible to return to qgis 2.4 OSGeo4W installation when I have qgis 2.6? I want with advanced installer. Thanks,
2
votes
1answer
81 views

remove unwanted areas which are not inside the boundary of second raster

1 raster layer - global map ; 2 raster layer - berlin I cropped out 1 layer using extent of 2 layer and then overlapped these two layers however I see that 1 layer still has areas apart from ...
2
votes
2answers
392 views

Call output files in temporary directory through Processing Toolbox (python)

I need to create temporary files as intermediate output to be used with processing algorithms. So, I implemented this: Processing.runalgorithm("grass:v.to.rast.attribute", ........, None) This line ...
1
vote
2answers
408 views

Issue in the popdown box (QComboBox) in QGIS 2.6 Python plugin

I had developed a plugin that counts the number of features for a layer in Qgis2.6. When i load a layer say 'Airport' for first time and click the pop-down box in the plugin,it lists the airport ...
6
votes
2answers
815 views

How to symbolize features with NULL values in graduated symbology?

I have a polygon feature dataset, and an attribute from a different table that I join (one-to-one) within QGIS in order to symbolise the attributes as a choropleth map. However, not all polygon fields ...
2
votes
1answer
73 views

Does anyone have any tips on figuring out why a Vector Layer didn't load in Pyqgis?

This is a general question. I'm stepping through the pyqgis code and the layer isValid() is always False. I don't see any error messages showing any reason why it wouldn't load. Other similars have ...
2
votes
1answer
408 views

How to scale SVG symbol based on zoom level in QGIS?

I am wondering if there is a way to scale SVG files I have stored as blob in a Spatialite database according to the current zoom level in QGIS. My hope is to have the SVG icon resize itself when the ...
2
votes
0answers
171 views

Edit WFS-T layers ArcGIS Server in QGIS

I'm trying to edit layers from a service in ArcGIS Server through WFS-T in QGIS. But the AGS only allows writing in version 1.1 of WFS, while QGIS only connects to the WFS Server in version 1.0, ...
0
votes
1answer
151 views

QGIS 2.6 Crashed for my own plugin

I had developed a plugin that counts the number of features for a layer in QGIS 2.6. I am using Windows 7 os. It works fine when i loaded a layer. But when I remove that added layer and then if I ...
4
votes
1answer
351 views

QGIS “ERROR 6: No translation for Lambert_Conformal_Conic to PROJ.4 format is known.”

I am trying to clip a county DEM file using the PLSS Section shape files as mask layers... that is, I want it clipped to sections so that I can load my DEM into QGIS one section at a time, without ...
2
votes
1answer
241 views

Command line error and missing dependency in QGIS

I have two problems with QGIS 2.6.1 1) When i am trying to open command line i get error: An error occurred during the execution of Python code: Traceback (most recent call last): File ...
1
vote
0answers
155 views

ArcMap KML Multigeometry to Shapefile

I have been troubleshooting this issue for quite some time now. I have a variety of tools available to me: ArcMap, QGIS, as well as OGR2OGR. Unfortunately, I have not had any success with any of these ...
3
votes
1answer
318 views

overlaying raster layer hides my vector layers in PyQGIS

I loaded vector layers and rendered them without a problem but when I tried to add a raster layer as well the map suddenly only shows the raster image and my vector layers are missing. Anything I can ...
3
votes
2answers
397 views

handling QgsVectorLayer (pyQGis begginer question)

I have a simple question. I am trying to start with pyQgis, but I have found it really hard to get a GOOD api Documentation, simple but yet useful. The one of you who did programming in the old ...
2
votes
2answers
508 views

How to mask labels in QGIS using an inverted polygon?

I created a file consists of a raster (snow load) and a vector with municipal boundaries. I added a vector with the contour lines of the snow load. Labels represent the snow load (kN / m2). With the ...
2
votes
1answer
87 views

Isolate features within buffer of another feature - QGIS

I have 2 shapes - one representing line features of pipes, another of roads. I would like to create a separate shapefile consisting only of the pipes that lie within 20m of the roads. Only the ...
2
votes
1answer
59 views

How to deal with QGIS Time Manager error: no attribute 'animationFrameCounter'?

I am using QGIS 2.6 and using the time manager I get the error shown in the attached pic. Anyone knows what the problem is and could someone offer a solution? Many thanks Nicole!
2
votes
0answers
71 views

QGIS - line between ordered layer of points - take attributes of both points

I have a series of locations in time in a point layer. I want to make a line layer of lines between consecutive points that takes the attributes (in my case, a timestamp) of the 1 points it connects. ...
3
votes
1answer
803 views

How to generate random points with minimum distances between points in multiple polygons

I am looking to create random points for a random stratified survey. There are three different categories being surveyed; for each, I have a single shapefile, each containing a number of polygons. I ...
9
votes
1answer
434 views

How to visualize measure values along linestrings in QGIS?

I have a series of LineStringM geometries. The measure value represents slope (or stream gradient) at each point in the geometry. I love QGIS's robust styling options, but I can't find a way to render ...
0
votes
3answers
1k views

Unable to run R in QGIS 2.6 - rgdal unavailable for R 3.1

I'm attempting to use R within QGIS2.6 on OSX Mavericks but cannot get R to run because rgdal is not available as binary for R3.1.2 (see QGIS log output from R execution console below). I have ...
0
votes
1answer
248 views

QGIS - Understanding how to georeference NAIP CCM jp2 images with lat/lon

I'm a very new QGIS user and no GIS expert. I am having trouble getting jp2 images to align with a vrt raster I've created from SRTM images. What I'm trying to do: Overlay SRTM data with ...
0
votes
1answer
188 views

QGIS 2.6.1 doesn't load python plugins on Ubuntu after upgrade [duplicate]

I have experienced this scenario once before and now today, whenever I updated my QGIS installation on Ubuntu, it didn't reload python plugins under ~/.qgis2/python/plugins when started, only c++ ...
2
votes
2answers
529 views

Loading Vector Layer using python console in qgis

I am using qgis2.6 version and new to pyQGIS. I tried to load a vector file using python console in qgis. I don't know where I am wrong. The layer was not loaded and does not show any error too. Help ...