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

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how to divide a Area shapefile into multiple segment, so that each segment will be a seperate feature in attribute table? [duplicate]

I'm very new to GIS, I'm using QGIS and here's what I want to do: I have a shapefile of an area . I want to divide that area into multiple segment (not grid), so that each segment will be a ...
3
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1answer
209 views

What's the projection of this albanian military map?

I've received some very useful maps of Albania for my work (scale 1:25000) and I would like to georeference them in order to put them together to one Map for my destined regions. Unfortunately I ...
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2answers
187 views

Measurements across UTM zones, how to apply spatial parameters to a customize a projection?

I have a survey grid that spans 3 UTM zones. Using http://www.epsg-registry.org/ I can get an indication of what projections are available. Where can I find more info on the patterns of distortion ...
3
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1answer
87 views

Can I use predefined list of values from Postgis when I draw lines in QGIS?

Lets say that we have 2 tables in Postgis: Table 1 (PIPE): -ID -pipe_type_id -geometry Table 2 (PIPE_TYPE): -ID -type foreign key PIPE.pipe_type_id - PIPE_TYPE.ID Table PIPE is empty. Table ...
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1answer
333 views

Pie-Chart Coordinates in QGIS

I have a map of a region and I am plotting pie-charts (as diagrams) over every country in that region in QGIS (1.9.0). I also need to connect those pie-charts with lines (which I am creating in the ...
2
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1answer
94 views

Is there a way to add drop-down list of predefined variables to R-script menu in SEXTANTE QGIS?

I would like to create a drop-down list of variables (similar to what it is done for layers input) for my R script menu in SEXTANTE. Is it possible?
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1answer
452 views

Can QGIS read ESRI TIN file directly?

Can QGIS open directly a TIN file generated with ArcGIS?
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0answers
82 views

Is there a way to label a layer using its file name or layer name?

Is there a way to label a layer using its file name or layer name (if I'd change it in Layers window TOC)? I tried some functions but I'm not good on that. I have lots of shapes (lines) and it would ...
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1answer
293 views

OpenLayers Rendering Error [duplicate]

I'm using QGIS to render some air quality modelling results. I'm having issues with the OpenLayers Plugin whenever I have another vector layer active. The plugin works if it's the only layer in the ...
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1answer
119 views

Quantum GIS Standalone Browser

I don't think the QGIS standalone browser is working right on my computer. The only tab I can view is Param. The Metadata, preview and attributes tab are all grayed out. When I select a .shp for ...
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1answer
260 views

Convert / interpolate delimited text csv points grid to surface

I've got 12 delimited text csv files with regular pseudo-gridded points for temperature and salinity which look like this when zoomed in (inc distances) and this when zoomed out. I'm trying to convert ...
3
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1answer
109 views

How to extract coordinate pairs of crossing points of two polygons in PostGIS?

Extracting coordinate pairs of crossing points of two polygons in PostGIS Is it possible to extract x,y-coordinate pairs of crossing points of two overlapping polygons in PostGIS? Suppose there are ...
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2answers
157 views

Read raster value at mouse position

I have raster layer imported in QGIS. How can I read value of the variable represented by the raster at mouse position? I just have a new raster layer and I want to read values at random places to ...
2
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2answers
2k views

QGIS, Table Manager cannot rename column title

My current attribute table has a column whose title exceeds the ten letters maximum. I installed Table Manager, hoping I could rename the certain field to further use it (in order to add some ...
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2answers
468 views

How to search and move to feature in QGIS?

After solving how to search text string I need to move to the selected feature. Is it possible to do that?
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1answer
88 views

QGIS (Mis)Detecting Escape Characters in SLD files

Okay, I am just running into some trouble with the string literal functionality with QGIS's rule based styling. For example I have an attribute called LITH that equals 'BAS\b'. The rule where LITH = ...
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2answers
351 views

How do I successfully install the LecoS plug-in for QGIS 1.8

I have been trying to follow the instructions given here, but repeatedly get an error message pop-up titled "Mount" stating Access is Denied. Does anyone have a solution please?
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1answer
143 views

Image map plugin not working with point data QGIS

I have a point shapefile and I am trying to create a html image from it using the html image map plugin; however, I can not get it work. I get the error: Wrong geometry type Any ideas on this? ...
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1answer
1k views

How to install Sextante in QGIS 1.8 without Plugin Installer?

How can I install sextante (and where can I download it) if the Plugin Installer doesn't works? As I work for a corporation, I have some problems conecting to the official repository, and I cannot ...
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1answer
100 views

How to save 'No data value' to a QGIS layer style properties?

I have many raster tif files (100+) I found this link to the MultiQml plugin very helpful, from this post: Can I change properties of several layers simultaneously? However the 'No data' values does ...
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2answers
175 views

How do I gather X and Y co-ordinate data from a vector grid overlay in QGIS 1.8.0?

I have overlaid a 10m x 10m grid onto a UK Ordnance Survey raster map. I have set both raster and vector maps to the same CRS, (OSGB 1936 British National Grid; ESPG:27700). I have a csv file ...
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1answer
92 views

Ubuntu 'Manage plugins' in 1.9 (master) doesn't show 1.8 plugins

I'm using Qgis master on Windows 7 and more recently xubuntu 13.04. On xubuntu, the 'fetch python plugins' is missing, which Nathan just pointed out was intentional rather than a bug. My problem is ...
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2answers
484 views

Qgis - need to draw exact lines (mtrs) with fixed angle

I use GIS 1.8. I have the need to be able to draw exact lines and shapes on a bing map. (This is to project a yet to be build greenhous project on a map to show what i would look like). I have ...
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3answers
4k views

QGis: Merge intersecting polygons into one which are part of the same feature

I'm not a GIS professional so I hope I use the correct wording, at least I hope you understand my question. Let's say there are 5 polygons in the feature A. In the shape file there are more ...
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1answer
84 views

How do I prevent QGIS 1.8.0 changing my dbf table values when joining tables?

Im a newbie on GIS as well as QGIS. I have a table of data saved from Excel as dbf format. After dragging and dropping the file into QGIS and then opening the attribute table, all values less than 1 ...
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4answers
825 views

ArcGis Trace Tool for QGis?

is there any tool in quantum gis that traces a line like the trace tool (Editor Toolbar) in arcgis? I want to draw a line and trace this line back so that i get the beginning and the end of the line ...
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0answers
24 views

Creating a buffer based on area (i.e. sqm) instead of distance [duplicate]

Is there a way in ArcGIS 10.1 or QGIS (or any add-on) to create buffer based on an area (i.e. sqm) rather than using buffer distance? I'd like to create a buffer of let's say 5% of the area within the ...
7
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1answer
215 views

Is Python essential for working in QGIS?

I am a beginner in QGIS. I Generally have a doubt: to work in QGIS is it necessary to know Python? whether i am asking we should know to write python programs to make certain modules run?
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1answer
701 views

Fetch Python Plugins missing

I'm running QGis master v1.9.0 on xubuntu and the 'fetch python plugins' option is absent. This guy had this problem with vanilla 1.7.5 but fixed it by upgrading to 1.9.0 master. Nishant had this ...
4
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4answers
1k views

How to get vector data from OSM to use in QGIS?

How do I get data from OpenStreetMap which I can then edit in QGIS layer by layer? What is the best OSM output and what / how do I get to a suitable input for QGIS? OR...is there another appraach to ...
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1answer
159 views

QGIS Layers Not Lining Up

I am new to QGIS, I have been using ArcGIS for most of my maps. I have two layers that are not overlapping properly. One is a shp file from a GIS clearinghouse and another from a delimited text ...
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0answers
98 views

Is it possible to undertake spatial clustering with QGIS?

Is it possible to undertake spatial clustering with QGIS, and also end up with proportional symbols in a quasi 3-d symbology?
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1answer
2k views

How to search text string and select item in QGIS?

I have a table attribute with complete roads name. I have to search items by digiting a part of the road name and I need to colour all the items selected. eg: ROAD NAME: / road 01 / road 02 / road 11 ...
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1answer
70 views

Using an image file as a placemark in qgis

I am making a map of sports clubs in London. I have each club's crest as image files (tiff) and want to make the placemark symbol using these images. I know it's possible to upload images in the SVG ...
2
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1answer
221 views

QGIS and ArcGIS on the same PC

I work for a small non profit conservation organization and we have a reasonably high turnover of people... so it stands to reason that some people don't want to change from a preferred program. this ...
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1answer
73 views

Get the ID of polygon in edition sessions of QGIS?

I did a Qt custom form for QGIS which contain a QlineEdit that must get the ID of the current polygon in edit session. For example, I start edit sessions I draw 3 polygons when the Qt form is opened ...
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1answer
123 views

How to write a expression in field calculator for finding $X and $Y?

I'm trying to calculate the lat/long of points using the Q GIS field calculator.Nathan W suggested to First, save the layer as WGS84 and import it again. Then in the field calculator you can use $x or ...
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1answer
435 views

How to resolve error “Handle bad layers” in QGIS?

I'm new to QGIS and have been seeing what it can do for me – seems good. I imported shape file data from a UK Ordnance Survey data file and saved the file in a new folder. It was very good, doing all ...
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1answer
141 views

Installing raster resampling module in QGIS 1.8

On the website of Sourcepole, I have recently come across the case of resampling images in Quantum GIS. Because I am rather a beginner in GIS software I would like to ask you for information about how ...
0
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1answer
77 views

Table calculation in QGis

I have a shape file with the attribute "yield". I need to know the math difference between yield (id1) and yield (id2)...then yield (id2) and yield (id3) and so on... I hope you understand what I ...
0
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1answer
107 views

Why is the CSVT file changing my real values to null?

I made a CSVT file to change desired real data to string data. After importing the original CSV file, that was linked by file name to the CSVT file, the string data appears as normal however all the ...
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1answer
642 views

Can I export QGIS basemaps as raster in ArcGIS 10.0?

I'm mapping a National Park in Malawi using Quantum GIS as with the plugin I can get the images from G.Earth (I need to see the vegetation). Since my supervisor is using ArcGIS 10, do you know if ...
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1answer
82 views

How can i detect the number of polygon is drawed in a edit session in QGIS

I am working with qgis 1.8 and i want to know how many polygon drawed in one edit sessions is there any signal emitted with qgis ???
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0answers
110 views

Action: open file from database

I have an image stored in a db (postgres / bytea). Is it possible to display (open) this image with a qgis action? In Qgis I have a (postgis) layer open, one attribute is the id of the image in the ...
0
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1answer
184 views

How to draw a custom map on top of base layer

I'm looking for the easiest way to draw a custom layer and export it as a tile cache. Basically what I would like to be able to do is load a base layer, and then draw objects and annotations on top ...
3
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1answer
217 views

Creating a radius of influence around points

I have a vector file of points. What I need to do is create a circle with a radius of 12km round each point. Would it be possible to then find out what percentage of my total map is covered with ...
2
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2answers
327 views

How can I create a multipoint geometry in QGIS?

I've got a Spatialite layer in QGIS with geometry type MULTIPOINT. Now I'd like to add some data in this table in the 'usual' way, so by doing multiple clicks in the map (e.g. left-click, left-click, ...
3
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2answers
325 views

How can I turn islands into individual features in QGIS?

I have what seems like a pretty straightforward task in QGIS: I have a shapefile that, in some cases, groups multiple separate landmasses into a single feature. For example, the Hawaiian islands are ...
2
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2answers
582 views

How do I prevent Qgis from being detected as “not responding” when running a heavy plugin?

I use the folowing line to inform the user about the status: iface.mainWindow().statusBar().showMessage("Status:" + str(i)) The plugin takes about 2 min to run on my data set but windows detects ...
2
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1answer
148 views

Why is this line split in two?

Even though this is a single line, it is stored as a two-part polyline. I can split it and rejoin at the break, but whatever I do it won't join the two into one line. (This is most obvious if you turn ...