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

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2
votes
1answer
110 views

How to get a list of all projections that are currently available in QGIS via the PyQGIS-API

i'm building a QGIS-Plugin and i want the user to choose a CRS out of a combobox in which the coordinates he would enter into some textfields are represented, so these can be converted into another ...
1
vote
3answers
1k views

Exporting 2 shp layers to geojson using quantum GIS

I will explain with an example: I have 2 shp files for Tanzania. Tanzania inland waters http://www.diva-gis.org/data/wat/TZA_wat.zip Tanzania administrative boundaries ...
3
votes
1answer
158 views

QGIS not creating new profiles correctly

QGIS 1.8 is not creating new profiles correctly under Documents and Settings. QGIS support files are also missing in My Documents for newly created profiles. I just tried to copy the missing files ...
7
votes
1answer
389 views

Calculating Maximum Distance from Centre of a Polygon to the Boundary of a Polygon

I have a polygon ready in QGIS. What I want to do is to calculate the maximum possible distance in kilometres from the centroid of the polygon up to the boundary of that polygon. I need two things: ...
0
votes
1answer
204 views

Why are layers not overlapping to each other inspite of having same CRS? [closed]

I am new to QGIS and working with QGIS 1.7.3 version, I have my all layers in WGS 84 CRS but even though they are not overlapping to each other, What should I do ?
6
votes
1answer
236 views

how to aggregate the rates, represented by points, within X radius

the point represents rates like 10%, etc. (this was also pretty clear from 2 years ago) -- been trying to do this for 2 yrs... the points dont represent numbers of events since they are rates ...
1
vote
2answers
416 views

Where are Print Composer Template files stored?

When I saved my Print Composer template, I cleverly navigated to a logical (to me) folder among my documents to save it. Now I find that it does not show up on the list of Composers under “File”. Can ...
3
votes
1answer
142 views

How I can incorporate results of histogram stretching into georeferenced image?

I have one channel 8 bit raster and when I open it in QGIS with histogram stretching "on the fly" it looks fine. How I can recalculate original raster accordingly changed histogram?
4
votes
1answer
317 views

How can I Enable Google Earth 3D features in QGIS?

I want to ask if there is any plugin or any other way where I can use Google Earth features in QGIS. When I'm saying Google Earth features I mean to be able to see roads, towns, etc and to be able to ...
2
votes
2answers
198 views

Does QGIS georeferencing set to magnetic or grid north for British National Grid?

I have just been georeferencing a map on QGIS using British National Grid and it is not lining up with the vector maps I downloaded from OS. I used the 'From map canvas' option and used 'Linear' ...
4
votes
3answers
2k views

How to extract raster values and create new raster in Qgis?

I want to extract certain values of a raster image in order to create a new raster which then should only contain the extracted/chosen values. How to do this in QGis?
2
votes
1answer
185 views

Inland / crater watershed delination

Even though watershed delineation is a quite popular matter here, I have what seems to be a somewhat unusual demand. I start with a DEM which is constituted of a series of craters, all centered on ...
1
vote
0answers
103 views

Problems with the scalebar not CRS related in QGIS

When I add one layer to the map, open it in the print composer and add a scale bar the scale bar is fine. I can add layers (with the same CRS) and everything is fine. Once there are two layers in my ...
6
votes
1answer
608 views

Is it possible to conduct a flood model analysis with QGIS using a DEM?

Is it possible to conduct a flood model analysis with QGIS using a DEM? Need to simulate rising water levels on a 250k map.
1
vote
4answers
468 views

How to create internal polygon without overlap on QGIS1.8.0

I would like to create new polygon inside the existing polygon. It does not means donuts polygon. I would like to have two polygon without overlapping. I can create if I don't check "Avoid ...
5
votes
1answer
350 views

Is it possible to put scale(ex; 1:10000) at print composer on QGIS 1.8.0

I would like to display a cartographic scale (e.g. 1:10,000) in the print composer. I can set the scale from map tab. After setting, I can type by myself as Label. Is it possible to put scale ...
15
votes
4answers
349 views

Is the term “Quantum GIS” trademarked?

We need to link to Quantum GIS on a major official website. My legal department asks me if "Quantum GIS" is trademarked. Is it? Thanks -- Alex
6
votes
2answers
956 views

QGIS or Postgis - How to split polylines with a point layer?

In QGIS, I would like to split the polylines in a layer loaded in the workspace with the points in another loaded layer. If a point intersects a polyline, this polyline should be transformed into two ...
3
votes
1answer
361 views

How to increase resolution of DEM rasters?

Thanks to the fine folks here at the GIS SE, I have managed to batch process a load of ASC files into raster hillshade TIFs. However, while they look fine on screen, when printed they are very ...
1
vote
2answers
429 views

QGIS create layer with the points of the beginnings and ends of a polylines layer (without duplicate points)

In QGIS, i would like to create a new layer containing the beginning and end points of a polylines layer, but without the duplicate points that would result of adjacent polylines.
0
votes
1answer
96 views

Alternate option for a Data Player plugin for GPS in qgis

I found a plugin for QGIS to play a GPS Track. (Data player plugin).The Problem is I can not read .gpx File with this plugin. Is there another option?
1
vote
0answers
324 views

Connect QGIS to MSSQL view (i.e. not a table)

I've got a MSSQL view containing data I want to show in QGIS. The view transforms a BLOB field containing WKB that is in one of my tables into a SQL geometry, which QGIS will be able to display. ...
5
votes
1answer
491 views

CAD Like functions in QGIS

Is it possible for a script to be built that will use a reference point and have it draw several polygons based on distance and bearing, then assess the terrain under the polygon for highest obstacles ...
2
votes
0answers
134 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 ...
1
vote
2answers
146 views

Put color for raster data(aspect.tif) on QGIS1.8.0

I create aspect.tif from DEM file. I could put the values(0 to 360)from contrast enhancement. I could set color from color map(freakout or Pseudocolor). In here, the data is shown by only 4 colors. I ...
8
votes
2answers
432 views

QGIS Categorized Style: Rearranging values so that it doesn't go 57,58,59,6,60,61

I have a a column of data that I'm trying to display in the Categorized Style but when QGIS orders the values it ranks them, for example, 57, 58, 59, 6, 60, 61, 62.... Is there a way to rank them in ...
4
votes
1answer
286 views

The number of digit of decimal point when you calculate area of polygon in QGIS1.8.0

I would like to change the number of digit of decimal point when I calculate area. For example Now: 32.456677 Ideal: 32.46 I try to adjust "output field width" and "Precision" These don't work well. ...
5
votes
1answer
645 views

Create a new vector layer that fills space between other polygons in QGIS

I inherited a clipped (500m radius) land cover map containing vector layers of different land cover categories such as buildings, grass, roads, etc from a colleague. The empty (white) space in ...
0
votes
1answer
230 views

Can this WPS be used in QGIS?

is it possible to integrate the following WPS-LINK in QGIS? http://gdz.bkg.bund.de/wps_koordtrans?REQUEST=GetCapabilities&SERVICE=WPS
2
votes
1answer
170 views

How to add point coordinates to a non geo-referenced csv file?

I have a csv file with information but not georeferenced. I'd like to load it in QGIS and add points (with coordinates) in the same file and later save as a shapefile. Is there any way to doing that ...
5
votes
2answers
155 views

Using field calculator to delete specific contours

I have 3 contour shapefiles with 25m, 50m and 100m equidistance. Now I want to delete in the 25m-shp-file every **50m and **00m contour and in the 50m-shp-file every **00 contour. How can I show them ...
0
votes
0answers
152 views

Why can't I see some polygon labels?

I create some features of polygon. And then, I put label with labeling from tool bar. I could confirm label of few features. On the other hand, I could not see the label of another features. I try ...
3
votes
1answer
235 views

How to prepare road network for routing in QGIS or GRASS

I have been working on a road network and I want to run shortest path algorithms on it. One problem is that some lines come very close to each other, but are not connected. Is there a way to connect ...
18
votes
1answer
878 views

Gravity/Huff model tools

I am looking for a way to simulate a gravity model using a point-based layer. All my points are assigned a z-value and the higher this value, the larger is their "sphere of influence". This influence ...
5
votes
1answer
1k views

Is QGIS Supported on Windows 8?

Can QGIS be installed on Windows 8? I'm going to buy a laptop with Windows 8, but I have no idea if Windows 8 can run QGIS.
6
votes
2answers
1k views

What's the Workflow for buffering in meters/km using WGS84 layers?

I'm a little bit new to GIS, so bear with me a minute.... I'm using QGIS 1.7.4-Wroclaw and working with an SHP layer in WGS84. I want to buffer out to a certain number of kilometers from this layer ...
1
vote
1answer
104 views

Raster menu does not have any tools in QGIS

in raster menu in QGIS, only raster calculator is available, how to get other tools, like wrap (reproject) please see the image for help. help me to get this.
6
votes
1answer
251 views

QGis Making Column Value of Attribute table unique

For a shapefile, I have a field named id with the following contents in it: 1 1 2 2 I want to make these values unique such as: 1 2 3 4 Is there any way to achieve this in Quantum GIS (using any ...
2
votes
1answer
145 views

How to best execute the same query on many different vector layers?

I have some vector layers in my project and I need to separate the polygones by area (I need a copy of all shapes > 2ha). I know how to do this for each separate layer (query) but is the a tool to do ...
3
votes
1answer
1k views

Export to new projection in QGIS 1.8

I would like to use QGIS to convert a CSV file from UTM to lat/long. I imported the CSV file with the "Add Delimited Text Layer" plugin. This works fine, the data looks like it is projected properly ...
5
votes
2answers
1k views

How do I use QGIS python console to iterate through simple layer queries and png outputs?

I'm really new to QGIS coding and I'm having a hard time finding (especially) the api classes/functions to carry out actions of the Query Builder window. I'm basically trying to do this: Iterate ...
5
votes
1answer
227 views

What tool do I need to have satellite background images to draw features of a postgis database?

What tool do I need to have satellite background images to draw features of a postgis database? I looked about Geomajas but seems very complex for what I'm trying to do. I have osm data imported in ...
3
votes
1answer
224 views

How to filter layer of osm data?

I have a table osm_roads that has a column named geometry geometry geometry(LineString,900913). If I want to filter a city to draw districts, I cannot do it by geographic coordinates? What if in ...
1
vote
1answer
564 views

How do I copy all feature attributes to a feature in a new layer?

I'm trying to create a new layer in QGIS based on an existing layer. The new features should have all the attributes of the corresponding features in the original layer. I've been trying to use ...
2
votes
1answer
165 views

How to fix the “The inserted Ring is not contained in a feature”?

I am trying to add a ring in a feature in a shapefile. This feature is a single part feature but has already a few rings. When I try to add the new ring, I have the error message : "The inserted Ring ...
3
votes
2answers
548 views

Can python read the value of a cell in a spreadsheet? [closed]

Can python read the value of a cell in a spreadsheet? The simplest example would be a script that ran a buffer tool on a given shapefile. For the distance parameter, instead of just using a number ...
2
votes
2answers
467 views

shapefiles in QGIS and ArcGis

Hi I'm working with a set of shapefiles and have some problems with the "align" of them in QGis when I load Openlayeres to reference some points. OLs has an straight horizontal baseline but the ...
2
votes
1answer
136 views

Can QGIS be installed on a Server

My question is whether QGIS can be downloaded and installed on a server for multi-user access. Rather than installing the software locally, can QGIS be stored on a server and accessed by many?
3
votes
2answers
427 views

Creating seperate layers out of one big polygon shape by using attributes

I try to explain may problem. I have a big polygon shape (> 200 fields). I have the owners of these fields in a column. I need the seperated shapes for each owner. Is there a tool to do that? Is it ...
1
vote
2answers
150 views

Making Multipart Features to Unique features

I have a layer with two lines crossing over each other. I create intersection point over them and then create a buffer for a specified distance and then using difference tool, I delete the buffer ...