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

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0answers
151 views

graduated pattern polygon fill

I'm sure this question is really really basic but I appeal to you because I hate the idea that I have spent 20 minutes trying to do such a simple thing... All I want to do is style a polygon layer by ...
2
votes
2answers
207 views

Looking for Floodplain Modelling instructions

I'm really new to GIS, yet I have a project that I am doing that is GIS entensive. I want to do a flood plain (for a river whose shapefile i have) and publish whatever output (its a map i presume) ...
1
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1answer
1k views

How to change vector attributes values?

I want to change vector attributes values. i could not get the command fet.setAttribute indeed, it is mentionned in http://hub.qgis.org/issues/7223 that: "The QgsFeature instance now must be ...
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3answers
2k views

How to rasterize a vector map?

I am looking for a way to create a raster grid from a vector map. I have a map consisting of shapefiles which I want to export as a raster with UTM coordinates. I was thinking of something using the ...
3
votes
3answers
129 views

Automated way to join

I have river networks (polyline) of several adjacent countries as shapefiles that almost match up at the borders, but not quite. Is there any way to automatically connect them to a consecutive river ...
3
votes
1answer
2k views

How do I find vector line bearing in QGIS or GRASS?

How can one extract the bearings from a set of lines in a vector file? I'm trying to find the bearings of several straight vector line segments (simplified contour lines, actually) and can't figure ...
3
votes
2answers
1k views

PyQgis overwrite shape file and adding layer to Qgis

I am creating a shapefile in python by: driver = ogr.GetDriverByName('ESRI Shapefile') datasource = driver.CreateDataSource('c:/temp/toke2.shp') layer = ...
6
votes
1answer
146 views

Previewing File Geodatabase in QGIS Browser - Is it Possible?

Can I Preview/look at file geodatabase attributes in the QGIS browser if I have installed QGIS using OSGEO4W installer and FileGDB API? Currently I can add/edit file geodatabase feature classes to ...
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0answers
172 views

about intersection function of QGIS

I used QGIS digitization function to create polylines. Then I need to find the intersection points of these intersected lines. I used the function under the vector editing menu. But I couldnt do it. I ...
2
votes
1answer
200 views

How to fix distortions for Baden-Württemberg?

I'm working in an area in Baden-Württemberg, Germany. I loaded some OSM data in QGIS but the map display is distorted. I tried ftools define projection with many different projections but nothing ...
1
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0answers
31 views

How to load more than the standard tools to the grass toolbox?

I need to know how I get all the grass tools into the grass toolbox of QGIS. Is there an easy way to do this? I tried the sextante toolbox. After an update sextante doesnt work (python errors). For ...
0
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1answer
220 views

How do I style lines to show gradient colors for two attributes?

I have a layer with the city streets. I have a database with traffic values, including traffic going into the city and traffic going out from the city. I need to show the street links with different ...
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0answers
194 views

Help in GRASS/QGIS/Python

I have Idea about ArcGIS, and a bit of QGIS and zero programming knowledge, which I am trying for thesedays. I saw GRASS GIS and have started working with shapefiles, which are not being loaded... :( ...
2
votes
1answer
131 views

How to represent two fields of the same states or district layer using different color borders and fills in QGIS?

If I had a set of data in QGIS that was gradually shading a state or district the exact way I wanted -- but I also need to portray more information about that state or district with additional colors, ...
1
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0answers
667 views

QGIS plugins with python dependencies [closed]

Problem: I have a Windows XP machine with Python 2.7.3 installed at ‘C:\Python27' and the scipy module installed at ‘C:\Python27\Lib\site-packages'. I installed QGIS 1.8 recently and started ...
1
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0answers
306 views

View PostGIS geometry in QGIS

I am a newbie to GIS systems so please be patient. I have a PostGIS database set up with a spatial data table. One of the columns is of Geometry type and contains Points with SRID 4326. I want to ...
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votes
2answers
205 views

styles when merging shapefiles in qgis

Trying to create something for mapstory.org It wants it in all one shapefile. So I create a polygons and lines (with time attributes) in qgis 1.8 Then merge them all into one shapefile, how can you ...
0
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2answers
1k views

Mysterious Problems with .IGE file [closed]

I'm trying to manipulate an .IGE file, which I understand is a raster data format developed by Erdas Imagine. The data I've downloaded is the National Land Cover Database (NLCD) 2006 Percent Developed ...
3
votes
1answer
622 views

How to get a QGIS useable style file from OS .xml and .xsl files?

Ordnance survey provide some style files to support their vectormaplocal product. The style files appear to come in pairs, similarly named but one with a .xml extension and the other .xls The two ...
2
votes
2answers
1k views

How to set/save the extent of a map in QGIS?

I'm creating a bunch of maps with TimeManager in QGIS in order to create an animation. In order to overcome some of the limitations of TimeManager for dealing with raster files, I'm creating ...
0
votes
4answers
336 views

Coordinates conversion doubt

In QGIS do I have a EPSG:4326 shapefile that shows the coordinates "-7148300 -3688500" and I need them in the format -64º -31º for further processing in a geodjango app. However using ogrinfo I get ...
1
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1answer
245 views

Converting Heatmap into Grid of Points to regenerate less accurate Heatmap?

Question: How do you take a heatmap generated using a GIS software (arcgis, qgis...) and convert it into a uniform grid array of points which can be used to regenerate the heatmap (although with ...
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0answers
122 views

About spatialite views and Attribute table

I try to use views with spatial column in spatialite. I can connect to spatialite database and load the layer without problems but when I try to view data in Attribute Table I can't get eny data; all ...
0
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0answers
318 views

Select record from table attributes in QGIS and Python

Can anyone tell how I can access to the attribute table of a shp and select a record from a specific row and column using Python (with console or a script). I've been looking for in the qgis API, but ...
2
votes
2answers
171 views

Is there a way to visualize a convexhull in qgis 1.8 lisboa?

There is no way to visualize a convexhull in qgis 1.8 lisboa? I have tried following views in Postgis 1.5 I was told to use an id column to publish it in Qgis. If you not use an id column, u cannot ...
3
votes
1answer
315 views

How to delete one polygon from a multi polygon record in a spatialite database using QGIS

I have a spatialite database with multi polygon records within the database. When i try to edit these records i cannot delete just one of the polgons for a specific record. It only allows me to delete ...
1
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1answer
100 views

Did anyone manage to use time manager with dates before 1900?

a simple question. Did anyone manage to use time manager with dates before 1900? Other than the solution suggested by Anita in Is it possible to change the year range of time manager in QGIS?
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1answer
278 views

QGIS cannot view raster loaded to PostGIS through raster2pgsql

I tried to load a raster GeoTIFF image to a PostGIS database using "raster2pgsql" following the OpenGeo Suite Manual. The command I used is: C:\>raster2pgsql -s 4283 -I -C -M "C:\Program ...
2
votes
1answer
122 views

Can TimeManager animate a large number of rasters in QGIS?

I understand that as of a year ago, the TimeManager plugin was not intended to handle more than a handfull of rasters. This post is in blind hope that this has changed! I'm trying to create a map ...
0
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0answers
41 views

Convert Shp to Dxf with QGIS [duplicate]

8.0. I have asked this before and seen similar but not the same (all of which I Have not got an answer to so not a duplicate). But is there a way to export a shp as a dxf so that it will not crash ...
5
votes
3answers
278 views

GIS file format for space and time data?

I need some advice with GIS file format choice. Here is my problem: I have about 100 stations. At each station water temperature is measured daily for 1 year I want to load this data to QGIS and be ...
2
votes
2answers
980 views

get value from attribute table and change symbology with QGIS and Python

I'm newbie developing plugins for QGIS using Python, this is the first one and it is very frustrating hehe. Ok, this is the situation, I have a 1 point layer in QGIS. Its attribute table has 4 fields ...
2
votes
1answer
676 views

How to invert polygons (or other options for exterior styling)?

I have a shapefile containing many polygons that I want to use to mask a raster. I have tried gdalwarp -cutline <shapefile> -crop_to_cutline -srcnodata -9999 -dstnodata -9999 ...
4
votes
4answers
404 views

How to create a label formatted like “ 1,000' ” from a numeric field?

This question builds on a previous question I came across at gis.stackexchange: How to easily edit attribute data using Regular Expressions? Perhaps someone can point me in the right direction? I ...
1
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1answer
506 views

How to install TimeManager for QGIS?

I'm trying to install TimeManager for QGIS. I can't find it under Plugins/Fetch Python Plugins and I have verified that the official repository is listed in the Plugins menu, so I'm wondering if ...
3
votes
1answer
305 views

How to get pixel size of canvas in QGIS?

How to get pixel size of canvas in QGIS? It is possibly by python? I mean this read rectangle area.
1
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1answer
458 views

Is it possible to change the Mouse Wheel zoom direction in QGIS?

I'm just starting to learn QGIS. I'm starting with the basic simple things. Coming from an ArcGIS background, I am used to the mouse wheel action zooming in and out the default ArcGIS way. QGIS ...
1
vote
1answer
498 views

How to write a CSV from Python console in QGIS?

I am trying to write out a CSV file from a vector layer made up of points using the python console in QGIS. I've tried the following command: QgsVectorFileWriter.writeAsVectorFormat(layer_Map, Folder ...
1
vote
1answer
416 views

How can a HTML table be stored within a database field as a BLOB, text or other value?

My Spatialite database has several thousand spatial polygon records In QGIS, each with a couple dozen field values. I also have many thousands more of additional tabular data relevant to those ...
2
votes
2answers
1k views

Layers with same coordinates not lining up [QGIS]

I have a project where I have a few layers (State of Texas, cities, roads, etc.). They are all resaved and projected to NAD83 / UTM zone 14N EPSG: 26914. The project CRS is also NAD83 / UTM zone 14N ...
1
vote
1answer
543 views

Changing symbology/color in kml when exported from arcGIS/QGIS [closed]

I have marked some points and used symbology in ArcGIS/QGIS... when I export the file to kml, the color/symbology changes and only single color/symbol remains. Is there any possible way that the ...
2
votes
2answers
214 views

Save a layer for each unique value using Python in QGIS

I have a map, in which each region is defined as an attribute of the map (I can select each region from the attribute table). I am trying to create new layers each one containing only 1 region using ...
0
votes
2answers
307 views

Calculating area gets a different result

I've calculated the area of polygons with QGIS by using ctr-i - geometry - $area. I've set it on real. The results seem fine, but I've noticed they differ from the area given when I use the ...
0
votes
1answer
478 views

Problem when compiling QGIS (with customizations) for Windows

I was able to customize a few features of QGIS in Ubuntu. Now I am trying to compile the same code on Windows, by following the installation guide given for Windows. I have downloaded all of the ...
2
votes
1answer
1k views

How to evaluate raster calculator expressions from the console?

How can I execute from the console an expression that should be used with the raster calculator? I'm searching for something like this: qgis.someRasterCalcClass.evaluate("boh@1 + boh@2", ...
1
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3answers
584 views

Looking for a simple method to find the shortest path with Shapefiles

I am having shapefiles for a particular map location, the shapefile consists of points and polylines. Now I want to find the shortest path between the points. What is perfect and simple method to find ...
3
votes
2answers
2k views

Simple automated way to split all lines in layer at vertices using QGIS?

I want to automatically split all lines in a QGIS layer at their vertices (like this). I've done a google search and found this article, which is quite close but the workflow is complicated. Because ...
1
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2answers
824 views

MMQGIS: How to make grid layer in meters not degrees?

I've read several of the posts on here pertaining to MMQGIS Create Grid Layer option, but I have not found information on how to make the grid based on meters veres degrees. I know how to manipulate ...
0
votes
1answer
95 views

QGIS: put vector values into separate layers?

QGIS 1.8.0 Mac: I've got a polygon shape file with values 1-5 in it i.e. contours. How do I get the polygons for value 5 into one layer, 4 into another... so I can assign each a colour and see them?
3
votes
1answer
202 views

Stuck while Using GeoServer WPS with QGIS

I have been using Geoserver WFS and WMS with Qgis for a longtime. Now i am trying to integrate WPS... I downloaded and activated WPS plugin for Geoserver. And i succesfully got result of buffer ...