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

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2
votes
1answer
223 views

QGIS “transform error” messages - how to stop them?

In QGIS, I am getting an error message every time I edit a node. Also, there is a lot of lag in performance. The message is: "Transform error caught: forward transform of (10990.308086, ...
0
votes
1answer
112 views

Distance-direction computation of lines with exactly/more than two nodes?

A distance and direction tutorial provided as an Answer at How to add Direction and Distance to attribute table? uses: xat (0 ), xat (-1 ) and yat (0 ), yat (-1) for start and end points of lines; ...
0
votes
1answer
96 views

How to open a shapefile linked custom metadata textfile within QGIS

I used a text file as a simple metadata for my shapefiles. It has basic information such as Source of raw data, Who can edit the file, Accuracy level, data category, Cost aquiring data, etc. The ...
2
votes
1answer
96 views

Why is “Join Attributes by Location” reporting different CRS (and running forever)

I have a point feature layer with ~240,000 parcel centroids. I have a second feature layer containing ~9000 subdivision polygons. I want to assign the name of the associated subdivision as a new field ...
1
vote
1answer
237 views

Different ways of saving color ramps in QGIS (xml, qml, csv), which should I use?

I started to use QGIS for personal mapping as a hobby (specially for planning bike routes), and I notice there are more than one way to use color ramps. There are styles, which can be saved and ...
1
vote
0answers
30 views

How do I dissolve to a predetermined number of contiguous geographies based on equal division of a value?

Let's say I have a layer that is the state of Oklahoma, broken up by county, and I want to dissolve it into contiguous regions of roughly equal population size, and I want to define how many regions ...
1
vote
2answers
334 views

How to change raster cell values within a polygon using QGIS GUI?

I would like to know how to change the values of raster cells which are within a polygon, leaving all cell values outside the polygon unchanged. I would like to subtract 1.5m from each raster cell ...
2
votes
1answer
477 views

QGIS 2.0 Plugin: Select and Identify a Single Feature

given is a layer with some nodes on it and every node has some attributes(name, id, etc...). For showing up the informations of a single node I can use the "Identify Feature Tool". Choose the tool, ...
-1
votes
1answer
75 views

Mapinfo and qgis file's datum problem [closed]

please refer to following link for the explanation of the problem I had. do you have any idea on this? ...
1
vote
2answers
227 views

QGIS howto create raster from map canvas easily

i have question ho to create raster from QGIS map canvas (what i seen in my qgis) easily. Now i have used print composer and after some luck i get whole dataset into map item, after that i throw lucky ...
0
votes
2answers
464 views

Batch merge large numbers of.asc grid files

I have >2.5k .asc grid files which I need to merge into a single overarching dataset. I would like to avoid having to convert them into esri grids first so was looking to use QGIS (v.2.0). I am ...
2
votes
1answer
331 views

Qgis & processing doesn't links with Grass, r or saga

After having formatting my computer (W7-64bits), I have re-installed QGIS 2.0.1-64 bits on it . But I can not use GRASS, SAGA or R via Toolbox (or Processing). I have checked the path in the Options, ...
0
votes
2answers
177 views

Conversion of diagonally adjacent pixels into one polygon?

I am trying to vectorize a raster whose digital numbers indicate different classes they belong to. ArcGIS and QGIS yield similar results: separate shapes out of pixels sharing the class that are ...
1
vote
1answer
840 views

QGIS Advanced String Filter Expression returns too many results

"GNR" is a string column and I expect the filter expression "GNR"='.11' to only return the feature with the value '0.11'. Why are the other features with values of '.110'and '.1100' included? Is ...
1
vote
1answer
313 views

QGIS snapping not working for me

I am new to QGIS, and this is a very basic question. I made a new polygon layer, to trace cadastral boundaries off a raster map. I want the polygon nodes on adjoining acreages to snap together. Some ...
4
votes
2answers
480 views

Binding between QGIS custom form (Qt Designer) and date/time field in a SpatiaLite database table

For my attribute table I created a custom form in Qt Designer. The table has a date field and a time field. In Qt Designer there are widgets for entering date and time. But what data type is expected ...
1
vote
1answer
167 views

QGIS Bookmarks not transfering with files

My students send me QGIS map files that when I open them have been stripped of the bookmarks. Is there a setting I'm missing or is the normal case.
0
votes
1answer
43 views

QGIS map file to be viewed on both mac and pc platforms

Im teaching a class where some students have QGIS installed on their macs and I'm using a pc. Although the file structure is the same mac reference files differently than the pc and I get data link ...
1
vote
2answers
150 views

Polygon inside polygon invalid in QGIS

Looking at this map data from naturalearth (part of Oman & UAE to be specific), each country is defined as a multipolygon. In this case UAE (in red) contains two polygons and Oman (beige) three. ...
0
votes
0answers
44 views

No visual after loading geotiff in Qgis Dufour

I installed the latest version of QGis 2.0 for mapmaking. Before I used the 1.8 version and I had no problems in loading Geotiffs. With the latest version, it loads the same files but it doesn't show ...
0
votes
0answers
29 views

Problems with WMS QGIS 1.8

Hi I have loaded WMS layers previously but i seem to have hit a brick wall. I am trying to load from either the Geological Survey Irelands website (near the bottom of the page): ...
1
vote
1answer
35 views

Show the changed CRS in the Qgis attribute table

I am a GIS newbie, so bare with me if this is a duplicated question. I could not find the answer anyway. I am using QGis to read a polygon shapefile with a Dutch CRS (EPSG 28992 to be precise). Now I ...
3
votes
1answer
319 views

How to create halo for a text in the composer

I would like to add texts with halo, in the composer (not in the map). Do you know a way to do it? I'm using QGIS 2.0.1 Thank you
2
votes
1answer
282 views

Import of NAS-data, (norm-based data exchange interface)

Is there any possibility to import nas-data in QGIS. NAS (norm-based data exchange interface) is a XML-based format. German cadastral-data is only available in this format.
3
votes
3answers
112 views

How do I split a shapefile efficiently into mutually exclusive sets?

I have a shapefile containing about 240,000 features. I want to split this into five files with no overlaps. My current approach is to write a non-trivial expression that defines the first subfile, ...
0
votes
1answer
275 views

QGIS 2.0 Howto copy raster data from a QgsRasterDataProvider to an OpenCV matrix

I'm hacking the half day arround a problem and that I' thought it was simple one. I'm using C++ (QtCreator) QGIS 2.0 und openCV2 on an 64 bit Workstation runnig Debian Wheezy. The Application I try to ...
2
votes
1answer
159 views

Is it possible to create a default workspace in QGIS 2.0?

I have been using QGIS for quite some time. It always happens that I change the position of toolbars and panels to make the workflow more efficient. But then when I close QGIS and I have to start a ...
2
votes
1answer
168 views

Analyse slope gradient from LiDAR .asc data

I'm new to using QGIS. I have purchased some LiDAR data which downloads as .asc format, is there a way to analyse the terrain slope angle from this data or does it need to be converted into DEM? ...
0
votes
2answers
111 views

Robust importing of shapefile into spatialite database?

I am trying to import shapefiles into a spatialite database using spatialite-gui. I am having problems with the types of the variables since spatialite-gui has no obvious way to handle shapes which ...
1
vote
1answer
94 views

draw multipart polygon with one surrounding border

As you can see on the image below, the waterbody is divided by the border line because it consists of several polygons. I could merge the polygon, but I dont want to change the shapefile. Is there ...
4
votes
0answers
53 views

How to setup default toolbars and menu item?

I need to customize the UI for a group of users at another office. I want to turn off a bunch of toolbars and menus that are not needed. I know how to save my configurations (Settings -> ...
1
vote
1answer
133 views

Why does the QGIS Profile plugin lack the profile graph?

I've searched but can't seem to find a similar issue with this plugin - the plugin starts ok and seems to run but I don't get any view of the profile or some other buttons in the UI as I've seen ...
1
vote
0answers
42 views

Geodatabase ESRI in Qgis 2.0.1 [duplicate]

I received data saved as geodatabase from Esri (10.x) and want to open or work with it in Qgis 2.0.1. The files are like following I read a lot in the forum about this subject but still have no ...
1
vote
1answer
2k views

How to export QGIS contour attributes in a DXF file?

I'm new to this. I have a .tiff data file that generates contours in QGIS. I save it as .dxf. The contours don't have any attributes or data. That's bad, because I want to make a 3D landscape in Revit ...
0
votes
0answers
33 views

Taudem one of the most important tool series doesn't work [duplicate]

Do you know if there is a way to get taudem working in the toolbox. I always get this Oooops! The following output layers could not be open Pit Removed Elevation Grid: ...
0
votes
0answers
130 views

QGIS 2.0 crashes: Add Delimited Text Layer

is there no chance to load the extension "Add Delimited Text Layer"? QGIS crashes as soon I try to install this extension. Using QGIS 2.0 on OS X 10.8.5, 8 GB RAM, 1,6 TB free of space… Thanks a ...
2
votes
1answer
153 views

Edit KML with the mouse in QGIS: is it possible?

In google maps, and more recently in Google Maps Engine Lite, you can create a Track/LineString by clicking with the mouse along a route, delete some intermediate point, drag the midpoint of a segment ...
2
votes
0answers
102 views

Joining csv file to vector layer in Processing modeler?

I am trying to join a simple csv file of values to a vector layer within Processing modeler. The match would be on an id held by both files. The csv file has no geometry. I can do this easily in ...
0
votes
0answers
223 views

MXD2QGS fails with 'ascii' codec can't encode character

I've tried to convert some mxd files to qgs but, I already have the same error: ": 'ascii' codec can't encode character u'\xe8' in position 57: ordinal not in range(128) Échec de l’exécution de ...
0
votes
2answers
167 views

QGIS 2.0, SpatiaLite: labels disappear after setting data defined position (x,y)

I added to my SpatiaLite table (.osm-import with the "standard" QGIS-OSM-Plugin) two empty columns x and y (double) to define manually the position of my labels (data defined labeling). But after ...
4
votes
1answer
93 views

Cutting Raster using two Polygons as Masks

I am trying to cut this raster in order to drop the outside of the walls white area and the area with the dots. I made one step using as mask the green polygon but i couldn't remove the inside of the ...
0
votes
1answer
380 views

Problem with MMQGIS in QGIS V. 2.0.1 - Attribute Join from CSV File

I've been trying to use the Attribute Join from CSV File function in MMQGIS, but it does not seem to work in Version 2.0.1. I've tried to join the same CSV and Shape files using V.2.0.1 running under ...
4
votes
2answers
479 views

What is expected QGIS 2.2 release date? [closed]

What is the expected QGIS 2.2 release date? It would be helpful to schedule my custom development in QGIS for "Relations" management.
2
votes
1answer
105 views

How to calculate correct angles for lat/lon points with the QGIS API?

I am trying to use qgis API to calculate the angle between two points by using function azimuth of class QgsPoint ( http://qgis.osgeo.org/api/classQgsPoint.html ), and my CRS is EPSG:4326 - WGS 84 , ...
2
votes
3answers
333 views

Why are some points in my PostGIS layer not displayed?

I have PostGIS table with some points and various attributes. Yesterday I added some more points to the table and now weird things are happening when I try and display layers built from these points. ...
2
votes
1answer
79 views

How to remove/disable last row/column of SRTM GeoTIFF in QGIS?

I've started using QGIS yesterday, and one of my main reasons to use it is to apply colormapped SRTM v4 over Google aerial imagery. Everything is working fine, except that SRTM v4 elevation tiles ...
4
votes
1answer
485 views

Why is tiff different in epsg 3857 and epsg 900913 in gdal

When I transform tiff from 4326 to 3857 and from 4326 to 900913 in gdal, I get different result(when display in Qgis) eventhough these two projections(3857 and 900913) should be the same. What is ...
3
votes
2answers
268 views

How to handle PostgreSql 1:m relationship data by using “Data-Driven Input Mask” QGIS plugin?

I have 1:m relationship tables in my PostgreSql. I like to show the main table attributes as well as the relational table attributes (like grid rows) in QGIS attribute-edit-form. What are the entries ...
0
votes
1answer
281 views

Field Calculator returning incorrect length and area values when QGIS project is reopened

Similar to Field Calculator returning incorrect length and area values, but as always slightly different. I have QGIS 2.0 and when I create a polyline shapefile, the field calculator returns the ...
6
votes
3answers
1k views

What format and settings to use for aerials photos in QGIS?

Following question which was more about handling Aerials with ArcGIS: Most Effective Format to Manage Aerial Photography for Viewing Only It seems there are 2 major options for storing / resampling ...