Quantum GIS is a user-friendly, cross-platform GIS application licensed under the GNU General Public License.
2
votes
0answers
45 views
Problems printing OpenLayers Pluggin Maps To Scale
It the print composer I can print all maps to scale and satisfactory.
However, when I add the OpenLayer, usually Bing Aerial, to the project I cannot print it out to scale.
I click the scale box, ...
2
votes
0answers
78 views
How to avoid creating corrupt Shapefiles during Editing?
I have one of my GIS technicians digitizing some lines in QGIS in shapefile format. I don't know how he did it (and neither does he), but somehow the shapefile became corrupt. It was creating random ...
2
votes
0answers
62 views
Raster area (QGIS) problem explained
I would like to know the area that each value in a raster has... The raster I have has values from 2-15 and I would like to know the area that each value is occupaying within my polygon... Thanks!
I ...
2
votes
0answers
31 views
How to analyze the signatures for a Landsat clasification with Sextante in Quantum Gis
I’m defining my training data for a Landsat classification. I´m digitalizing the polygons with the field data in QGis and I want to analyze the signatures of the Landsat images to avoid errors. In ...
2
votes
0answers
68 views
Storing features in PostGIS and then creating layers using queries
I have a whole set of line segments or tracks that represent real tracks or, in some case, boundaries between areas.
These segments form a network of lines on the map.
I have a number of GIS layers, ...
2
votes
0answers
83 views
Flow modeling and FOSS GIS; lahars and HEC-RAS
What are the options for FOSS flow modeling of dilute debris flows in QGIS or GRASS?
Have you, or can you refer me to studies where the authors, tested these models/plugins/functions/etc. for use in ...
2
votes
0answers
53 views
How to join nodes to network lines ( and not the other points)
I'm trying to do a shortest path analysis on my network. In order to prepare the network and attach polygon centroids to the roads, I used GRASS' V.NET operation=connect. the problem with this ...
2
votes
0answers
57 views
Can you set a QGIS print composer to render the map as default?
I have set up a number of templates for the print composer in QGIS.
In the Print Composer, there is the option to have the map image displayed in 3 ways:
as a blank rectangle with no updates until ...
2
votes
0answers
37 views
QGIS 1.8.0 Mac can't create ring
Can anyone spot what is wrong here? I've selected single feature, the existing rings are obvious, it's not intersecting anything (even a feature in another layer...
2
votes
0answers
116 views
Topology problems with QGIS/GRASS
*edited file links below
I'm working on several NGO projects at the moment, all of which are reliant on being able to use a district level map with some 490+ features, and I am running into some ...
2
votes
0answers
51 views
Why does Field Calculator put in all these 9's?
I’m trying to update some GPS point coordinates in an attribute table using QGIS Field Calculator. However, regardless of whether I do it by creating a new field or updating an existing one, I get ...
2
votes
0answers
68 views
draw lines with an angle inside a rectangle in python
I am trying to make a plugin for Qgis with python. I have the four corner coordinates for a rectangle. I want to give the user the inputs, line space and angle (0 -180 degrees).
With these inputs, I ...
2
votes
0answers
80 views
QGIS not rendering WMS layers
I'm a bit of newb' at GIS so be gentle with me.
In Qgis I've set up a wms for the British Geological Survey:
http://maps.bgs.ac.uk/ArcGIS/services/BGS_Detailed_Geology/MapServer/WMSServer?
Now ...
2
votes
0answers
87 views
WMS and Quantum GIS/ArcGIS
I periodically use a nice basemap served by the Utah state government in QGIS. Recently they upgraded their server from ArcGIS Server 9.3 to ArcGIS Server 10.1. Ever since then, I can't seem to get ...
2
votes
0answers
86 views
Transform RGB-Map to CMYK (qgis, opensource tools)
I want to print a map I made with qgis. For the print I need CMYK-colors but the print-composers pdf-output is RGB. How can I convert the RGB-map/-pdf to CMYK?
2
votes
0answers
47 views
How to use Memory layers in QGIS plugin to store results of Geoprocessing tools
I'm building a plugin to perform Multi Criteria Analysis (yes another one...). As part of my workflow intersecting vectorlayers is needed. I use QgsOverlayAnalyzer.intersection (a pity union is not ...
2
votes
0answers
137 views
z-Coordinate and interpolation plugin in QGis
I've a csv file that includes weather stations locations (x,y,z) and precipitation values. I loaded the file by using add delimited text and then converted it into a point shapefile WS84. By using the ...
2
votes
0answers
87 views
Export to shapefile qgis
I am trying to develop hotspot map showing point density in our gis based web application. After searching for an option I have decided to use v.kernel command. I have a table containing some point ...
2
votes
0answers
33 views
QGIS VPAT; Section 1194.21(c)
I am attempting to fill out a VPAT for QGIS so that it can be made more accessible in the federal IT environment. I could use some help and wanted to explore this venue as a means of getting it. If ...
2
votes
0answers
28 views
Automatic insert of project name into database
For every layer I've a field in my postGIS database that should be filled with the name of the current project and today I do this manually.
Is there a way to do this with the Commands that can be ...
2
votes
0answers
35 views
Is there a tool for automated quality assurance for vector data captured on raster data?
I wonder whether is any tool(or script) in ArcGIS or QGIS which allows to make an automated quality assurance for vector data captured on raster data?
vector data on binary raster:
2
votes
0answers
35 views
vector cropping failure
I’m trying to crop a vector contour layer using the instructions given at http://lists.osgeo.org/pipermail/qgis-user/2012-February/015294.html . I created a polygon in a newly-created vector layer, ...
2
votes
0answers
64 views
oil palm stand census algorithm
Anyone have experience in oil palm stand census using tree detection algorithm from satellite images in ArcGIS or QGIS? any references for usable algorithm? What is the accuracy? thanks for help.
2
votes
0answers
95 views
Plot csv data on a map
My boundaries shape file has the following attributes; CODE, PROVINCE, AREA, SHAPE_LENG and SHAPE_AREA (note that there are no geo- coordinates). My data on the csv file has the following fields; ...
2
votes
0answers
53 views
Looking for similar tool (like ArcGIS Diagrammer) in open source for QGIS?
Is there any diagrammer tool available (similar to ArcGIS Diagrammer) for QGIS?
thanks in advance : )
2
votes
0answers
61 views
select by location
When performing an overlay or intersect I would like to know if there is a way to ignore selection when intersection or overlay is less than a certain percentage of area or less than a certain number ...
2
votes
0answers
85 views
Adding polygon to existing database column
I've built a database with postgreSQL with a few geometry columns.
When I add some data to my non-geometry columns, I can see them in QGIS when I connect to my DB using postgis. Now, I want to add ...
2
votes
0answers
120 views
Can Nearest Neighbor Analysis help determine values for a Heat Map?
Given the below parameters (from Nearest Neighbor Analysis):
A) Is there a definite range my Radius value should be within?
B) Are there definite values my cell size should be near?
C) Is there a ...
2
votes
0answers
59 views
how to intersect a raster subset with a buffered vector layer (points) in QGIS?
I am a bit new in the GIS and qGIs sphere so maybe my question will look a bit naive, but at the same time it means it should probably be easy for most of you guys ;-)
I work in QGIS.I have 2 layers: ...
2
votes
0answers
73 views
Rendering a QGIS WMS layer in Firefox hogs the machine
I am less than a novice beginner on GIS Systems and am groping for answers.
I followed instructions for WIN 7 Install at both
...
2
votes
0answers
81 views
Using QGIS with EPSG:404000
I'm using QGIS with a flat-world approximation dataset and for my specific use, geometric coordinates on a 1 unit = 1 metre scale are perfect.
Unfortunately, QGIS doesn't have EPSG:404000 built-in, ...
2
votes
0answers
94 views
How to import PostGIS layer with geography type to QGIS?
I tried to import in QGIS a layer from a PostgreSQL table with a geography type column created through the extension PostGIS.
I noticed that QGIS doesn't seem to like the geography column...
Here ...
2
votes
0answers
83 views
Trouble with polygon to polygon “Join attributes by location”
I have two polygon vector layers - one of census tracts and one of water bodies. I would like to join a particular attribute from the water bodies table to each census tract, with the output being the ...
2
votes
0answers
190 views
How to join data from a CSV to a shapefile using QGIS
I'm new to GIS and new to StackedExchange.
I need help joining a CSV of Accessibility data to a LSOA shapefile in QGIS.
The process explained here does not work for me and I don't know why. The ...
2
votes
0answers
91 views
How to achieve better Dissolve results?
I applied the Vector>Geoverarbeitungswerkzeuge>Auflösen (Dissolve) on a zoning plan (see picture zoning plan). I used the attribute village name as the dissolving criteria. The resulting geometry for ...
2
votes
0answers
74 views
QGIS 1.8.0 suddenly sluggish/unusable on Gentoo
QGIS 1.8.0 has been working fine for a number of months. Then I upgraded my system generally, which possibly included upgrades to xorg-server and QT, and now QGIS is sluggish/unresponsive to the point ...
2
votes
0answers
89 views
How to Create a Vector Field from Separate u and v Data Files?
I am using Quantum GIS and trying to create a vector field using data from two separate netcdfs. One contains the u data, one contains the v data. Can this be done, and if so, how? Thanks.
Jason
2
votes
0answers
55 views
Qgis don't show geometries
When I select a object in a particular layer using qgis in order to get information about it, this object don't get resalted in red and in the qgis log a get the following error:
not found space ...
2
votes
0answers
293 views
Converting ArcGIS .mxd to QGIS .qgs without having ArcGIS installed
I was reading this link question How to convert an .mxd file to a .qgs file?. It looks as though this only works with ArcGIS 10? And the conversion needs to be done in ArcGIS 10. Does that seem right? ...
2
votes
0answers
84 views
Install Georeferencer Plug-in QGis 1.7.0 OS X
I'm trying to install the Georeferencer plug-in in QGis 1.7.0 on Mac OS X (10.5.8).
However the plug-in doesn't show up in the list. I have used "enable 3rd parties directory" and I have checked ...
2
votes
0answers
122 views
Intersect errors, memory issues in QGIS
my datasets are:
Track_02(simple road polyline shp)
***intersected with***
road_cat_cls(polygon for road categorization)
elev_rcls_poly(polygonized classified DEM)
slp_rcls_poly(polygonized ...
2
votes
0answers
47 views
Can QGIS give GeoJSON layers a meaningful default name?
When I add a GeoJSON layer to my QGIS project, it always gets the name OGRGeoJSON. This is in contrast with shapefile layers, which seem to be named after the file name by default.
Is there a way to ...
2
votes
0answers
74 views
How to cut lines in a shapefile following a GPX-source?
I have a OSM-Shapefile containing all roads of a given area. I need an overlay cut out of this source-Shapefile that contains only some routes that I want to highlight on my map. I have some ...
2
votes
0answers
49 views
Strange line appearing
I have this line in my project's layer which i cant make disappear:
I hope you can see it. In QGIS is much more visible. An it also appears on the print composer.
Any suggestions would be very ...
2
votes
0answers
65 views
Problem looking at tables within ESRI geodatbase
I installed the most recent OSGeo4W with QGIS 1.8.0 and GDAL 1.9.2 on my Windows 7 PC.
I can load an ESRI geodatabase (.gdb file) and I can get the window
"Select vector layers to add".
When I click ...
2
votes
0answers
66 views
How to make labels' size relative to the map in QGIS1.8?
I want to make my labels' size changed automatically with the scale of the map,so in the menu of "Layer labeling settings",I set the Text size" in map Unit".However,the labels in the selected layer ...
2
votes
0answers
93 views
How can I map polygon value distribution?
I'm surveying an area and have a z-value attached to each polygon. In comparison to the area I'm studying the polygons are quite small. What I'm trying to do is show the distribution of this value. ...
2
votes
0answers
89 views
How to geocorrect in qgis?
I need to fit a utm wgs84 tiff raster to a topomap in the same projection. I use GCP and it invariably fails. The first raster uncorrected rater superimpose well, the "geocorrected" raster is ...
2
votes
0answers
78 views
Sextante - SAGA- Shape to grid question?
I have a vektor shape (Index 1-5). After using the saga tool (shapes to grid) I'm getting a raster (values 1-5). The problem is that the NO DATA area is defined as 129. Is it possible to set 129 as no ...
2
votes
0answers
115 views
Generate QGIS maps automatic after updating an Access 2010 or Filemaker Pro 12 database
I want to develop a database which consist an interaction with QGIS. After updating the data in the database I want to push on a button and start a process in QGIS. After finishing the process in QGIS ...
