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

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2
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3answers
1k views

Is it possible to export cross sections from QGIS to HEC-RAS

Is it possible to create cross sections along a river in QGIS and then export the data to HEC-RAS? Thanks
2
votes
1answer
447 views

QGIS/PostGIS layer styles

I've made a plugin asking for login credentials to a DB. Once logged in, the plugin is loading some layers from the DB. In the DB there are both admin and "normal" users. I've saved two styles to the ...
0
votes
1answer
333 views

Dissolve large dataset in ArcGIS and QGIS

I have more than 80k point data. I have created few buffer from 1 to 5 km of them. Now I want to get the covered area by 1 km to 5 km buffered range. For this I have tried to dissolve those individual ...
1
vote
1answer
139 views

How can I change the coordinate system of gpx-points?

I'm working with qgis, v. 2.0.1. I have some points from a gps device (Garmin) and they already are in the .gpx format. Now I have two problems: First, I can't open the gps-Points with the "gpx-tools" ...
0
votes
0answers
236 views

Issue blocking QGIS feature form dialog with Python

I'm not sure where I'm going wrong with this python logic for a custom form in QGIS 2.0.1. There are a few things required by the validation function: that index of combo boxes aren't 0 (first index ...
2
votes
0answers
142 views

How to eliminate gaps and overlaps in a layer of SpatiaLite table?

I'm try to snap all polygons in a table to remove gaps and overlaps. I can remove gaps but get new overlaps. I have no idea what doing wrong... sorry, I'm new in SpatiaLite. I tried the following: ...
0
votes
1answer
75 views

Qgis 2.2 georeferencer always shows 0.00 dX, dY and residual. My fault or bug?

I'm georeferencing a map (jpeg) in UTM coordinates and everything works fine exept, i the referencer window doesn't give me any residuals or dX/dY values. When I change the coordinates of a point on ...
1
vote
1answer
180 views

Processing Script: now gives error in QGIS 2.2

I recently updated to QGIS version 2.2, and am now getting an error when running Processing scripts that worked previously (in version 2.0.1). Uncaught error while executing algorithm Traceback (most ...
3
votes
0answers
86 views

Using Field Calculator to Convert Data Type In Field

I am trying to convert a field that is listed as "String" because it was imported into QGIS as a CSV (rural poverty population percentages by county in NC). I need to convert the percentages field ...
4
votes
2answers
1k views

QGIS relations widget in custom form

I've just begun exploring QGIS relations option, now in version QGIS 2.2, details here: http://blog.vitu.ch/10112013-1201/qgis-relations This is a great implementation of something I've been ...
1
vote
1answer
827 views

Problem opening shape file in qgis

I am having a problem opening a shape file using QGIS using 'add vector later'. This is the error message i am getting: /Users/Conrad/AmerindianLands 2/Amerindian_Land_Karasabai.shp is not a valid or ...
2
votes
1answer
906 views

Adding graticules to the edge of the map only in QGIS

I would like to add graticules to a map, once it is in the 'print composer', on the border of the map, and not on the frame (my map insists on being smaller than the frame). I have managed to add a ...
0
votes
0answers
60 views

QGIS - Atlas. Outputs missing

This really teases me. Somehow the Atlas-function in Print Composer are missing some of my polygons from my layer, when doing a print. I´ve looked at them once again,- they are there, and the geometry ...
1
vote
1answer
421 views

Adding attribute list to combobox in a python plugin

I am developing a simple plugin at the moment which contains 3 combo boxes: comboBox_1 comboBox_2 comboBox_3 Combobox 1 & 2 lists the vector layers available, however I would like the 3rd ...
4
votes
3answers
164 views

How to shrink polygon on two sides?

I have a polygon which I know is a rectangle, although it may be at any orientation: I want to shrink this polygon by a third of the width from two sides, so that I just get the strip in the middle ...
0
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0answers
89 views

Raster format similar to ECW

I need an alternative to the ECW format that we currently have for a new series of Ordnance Survey maps. The ECW format looks clearer and less pixelated than the new maps in Tif format (in QGIS). ...
1
vote
1answer
73 views

Importing data into a project with a custom CRS incorrectly projected

I created a custom CRS for a project I am working on. I then started a new project, set to my custom CRS and turn on "on the fly" transformation. I import Rail data that I know is in my custom CRS, ...
0
votes
1answer
107 views

Georeferencing an aerial image based on satellite imagery

As part of a bigger project I need to georeference an aerial image based on a landsat image downloaded form usgs. I use qgis. can I somehow place the layers on top of each other and mark certain ...
1
vote
0answers
78 views

QGIS crash when selecting a Select Single Feature in attribute table

I'm loading several layers, styles and setting up some layer relations in a plugin that I execute. Once this is done I manually 'Select Singe Feature' on my map, switch to the "non-table view" in the ...
0
votes
1answer
386 views

Link Google Earth with QGis

I was wondering if it was possible to link Google Earth files (KML, KMZ) to a QGIS project. The main idea would be that if you'd add a point with coordinates in Google Earth, this point would be added ...
0
votes
1answer
1k views

What is the format expected by QGis for Latitude/Longitude in DMS?

I have been struggling with a csv file I need to import into QGis 2.2.0 (on Windows 7). The coordinates are in this format: LATITUDE LONGITUDE 424605 861204 395222 861206 303051 861219 ...
2
votes
0answers
93 views

Cannot Save Edits to File Geodatabase Replica in QGIS 2.2

When trying to edit a File Geodatabase Replica in QGIS 2.2, everything works as expected until the user saves their edits. When pressing save, all edits revert back to their original state with no ...
1
vote
2answers
311 views

How to select objects by N:M join?

I have a layer with some geometries and a data layer that defines an M:N relation. Is there any way I could select (on the map) objects that are in relation with specific id? Basically I would like to ...
1
vote
0answers
129 views

producing a bathymetric map in qgis with limited depths measurements

i am new to your community and hope you to find tips on how to work with the following project. i want to produce a bathemetric map (depths profile) of a water area. I do have aerial images and 3 ...
1
vote
1answer
233 views

Is it possible to link a QGis project with an excel file?

I have an Excel file with coordinates and I have used this file to plot the coordinates in QGis. I was wondering if it was possible to permanently link the excel file to the QGis project, so that when ...
2
votes
1answer
207 views

How to create polygons from a polyline graticule?

I'd like to make a polygon shapefile out of a polyline shapefile showing a graticule. However, using the "Line to Polygon" tool results in a peculiar...something: Other standard tools like ...
-2
votes
1answer
78 views

Interactive Gis application [closed]

I'm developping an interactive web(HTM5) gis application wich the user draw an element(circle for example)and extract data from base map(Open Street Map).The features would be: 1º Base Map like OSM. ...
2
votes
1answer
471 views

How to adjust QGIS attribute table view column width using Python?

I'm programmatically opening the Attribute table via Python through a plugin. All of the columns have a default width, but some of the data that I'm using do not fit. It's not enough to be able to ...
2
votes
1answer
276 views

Wrong lon and lat

I am using QGIS 2.2.0! I have shape file with wrong coordinates, it's had replaced x coordinate with y coordinate. For example my point feature have coordinates: 4830698,7496859 and right coordinates ...
1
vote
1answer
206 views

PyQGIS loading layer style with PostGIS

I'm loading layer styles from .qml files in a Python plugin. I'm about to switch to loading them from a non-local postgreSQL db. I've been looking at the (from QgsVectorLayer (v2.2)) ...
0
votes
1answer
94 views

Is it possible to do a query to multiple tables?

I have a point a line and a polygon layer. They have the same attribute table. Can I do one query that refers to all the attribute tables? So I wouldn't have to do every query three times. Thanks. ...
1
vote
0answers
69 views

Calculating Percent Overlap Between Distribution Maps

Hello there, I am currently trying to calculate the percent overlap (basically the total amount of overlap where these two species come into contact) between Lithobates catesbeiana (first image) ...
2
votes
1answer
73 views

Displaying QGIS layer after loading with Python

I'm successfully loading several layers with Python, but can only get to see them in the map window if I manually zoom to extent afterwards. Once the last layer is loaded I call zoom to extent in the ...
1
vote
1answer
173 views

Python.dll could not be loaded with PyScripter

I'm trying to configure PyScripter with QGIS. I've installed it using OSGeo4W and I'm following instructions to setup a pyscripter.bat file by copying content of qgis.bat file. I have the following ...
1
vote
0answers
87 views

Ubuntu Touch and QGIS?

I'm planning buying a tablet for running Ubuntu. There are little info on experience with Ubuntu Touch and QGIS and does it work? What I want is to run it on the tablet, drawing polygons etc on ...
1
vote
1answer
135 views

QGIS Custom Form: “Other” category in combo box replaced by line edit [closed]

I am trying to create a custom form for QGIS 2.0 with comboboxes containing an "other" category. I wonder how to provide a line edit to enter info replacing the "other" choice if chosen. Not sure if I ...
2
votes
1answer
72 views

Upright/Horizontal lables when labeling polygons at perimeter?

I have several polygons (circles) I want to label with their ID number. The label should be outside the circles so I use the positioning options "Use perimeter" and the tickbox "Next to the line (or ...
3
votes
0answers
335 views

Why does the QgsVectorFileWriter have probelms creating vector files? [closed]

I am using QGis 2.0.1 and have tried to create a new GIS feature file (SQLite, Spatialite, and Shapefile) of a subset of the data. I am then saving a copy of the style of this layer and applying it to ...
1
vote
1answer
83 views

Why do the raster band values have different values than the raster statistics?

I am working on a raster file (1 Band). According to the raster metadata, my minimum value is 0 and maximum is 7458. This seems to be confirmed by the Style options that return some category values ...
1
vote
1answer
70 views

Overlay polygon on raster and save as new raster with same resolution

New to GIS and trying to learn. I'm trying to take a blue marble raster, overlay a countries .shp file, and save an image with the original blue marble image and the country outlines "burned into" the ...
5
votes
1answer
199 views

How to open QGIS attribute table in form view using Python?

I've got a plugin where I load some layers. After the last layer loaded, I show the attribute table. However, I would like to select the form view and not the table view (see image). How can I do ...
1
vote
0answers
65 views

How to perform image classification with SemiAutomaticClassificationPlugin and BIP files?

I have multiband satellite images BIP format, Landsat TM/ETM containing 7/8 bands respectively along with a separate header file, some of them corrected by nearest neighbour classifier. I'm working ...
1
vote
0answers
42 views

How to disable log messages in QGIS

Is it possible to disable log messages in QGIS Dufour? When I work in QGIS 2.0, log messages increase to more than 2000 and it makes QGIS very slow. Then I save project and open it again, then QGIS ...
1
vote
1answer
35 views

Changing georef backgound colour

Working with a greycale scanned image: when I georef that image it rotates (expected) the blank corners are then filled with black. When the new image overlays I need to make those corners ...
0
votes
2answers
1k views

How to install PostGIS and OpenLayers plugins?

I am new to QGIS and have installed the QGIS v 2.2.0. For adding google map as a base layer I need to install OpenLayers plugin. I also need to add the PostGIS plugin for DB management purpose. Can ...
0
votes
1answer
51 views

How to find qgis2 folder to delete in ubuntu

How can i find the qgis2 in qgis and where it is installed, i had one error on when qgis open this error will occurred "[ERROR] Can not make qgis.db private copy" some links told delete the folder ...
1
vote
1answer
100 views

How to create a TAB with custom CRS using QGIS?

I meet problem about reproject in Qgis. I created coordinate user defined. i used version Qgis 2.2. I defined coordinate: Name: VN 2000 / 107.75 3degees Parameters: +proj=tmerc +lat_0=0 ...
4
votes
1answer
962 views

Continuous color band for a raster legend in QGIS composer legend

I'm looking for a way to insert continuous colour legend for a raster layer. I managed to create discrete symbols with values along the bar, but I would like to have a continuous bar with some values ...
0
votes
1answer
31 views

Join text with layer

In Mapinfo it´s easy to link a text-layer with a geometric layer by attributes with outcome as a new layer. Where and how to do this in Q-GIS?
1
vote
1answer
84 views

Transect with square polygons

would like to create with QGis 2.2 (german version) several square polygons (1km ²) that seamlessly connect to each other, so that a strip ( transect ) of 9km times 1km length results . ( I once ...