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

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1answer
74 views

How to measure and mark a line or point as a template QGIS?

I'm digitizing some of our sewer assets and need to be able to measure distance and create points. So, for instance, I have a sewer main that is 65m long. I need to mark a point at the 32m mark, then ...
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0answers
114 views

QGIS grabs incorrect field values for categorized style classification

as seen in the first image, the field values QGIS returns when I attempt a 'select by expression' are values found nowhere in the field in question ('FLD_ZONE'). Instead, it returns a selection of ...
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2answers
134 views

How can you insert a custom symbol?

How can you use a custom symbol for either dot density or proportional symbol maps in QGIS? Is there a way to import a symbol of your own such as a drawing or image that you can create or download ...
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1answer
217 views

How to change QGIS project color space

Is it possible to change the color model of an entire QGIS project from RGB to CYMK? I know that it's possible to change the color models of individual symbols/features (through the style manager), ...
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1answer
66 views

QGIS Raster Calculator dialog doesn't resemble that in documentation

I'm very new to QGIS. Raster Calculator looks (from online sources) like it ought to have all kinds of buttons and fields. Mine is rather stripped down. I have two rasters open, and I just want to ...
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2answers
2k views

How to avoid “Handle bad layers” message when using QGIS Flowmapper plugin?

In QGIS, if I close a project and try to open it a few days later I often get a message that says "Handle bad layers". This is very frustrating because when I open the project various layers will have ...
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1answer
251 views

How to change the size of Hex bins?

I am creating a map in QGIS and I am using a hex bin layer. To create this layer I used the MMQGIS plugin and created a grid layer. However, the size of my hexagons that I created are too small, and I ...
2
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1answer
818 views

Microsoft Access mdb “is not a valid or recognized data source” in QGIS

The answer to RyanDalton's question "Can QGIS read an ODBC connection?" explains how to establish a link in QGIS with an MS-Access table. Following his steps, I can establish an ODBC link (I ...
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2answers
1k views

Merge two rasters with no data value

I have two rasters: Raster A and B. Raster A has has only values of 0. The white area in Raster B are No Data values. I want to merge them to one raster (Raster C). So basically I want all pixels in ...
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0answers
398 views

How to compile QGIS with Oracle Spatial support for Linux?

I compiled it on Fedora and Ubuntu, but got error "Cannot get Oracle select dialog from provider." while trying to add Oracle layer. Packages in repositories don`t have oracle spatial support. Can ...
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2answers
180 views

Saving edits slowing down (QGIS 2.01)

QGIS 2.01 on Windows 8 I have a polygon layer which I edit in QGIS 2.01. Editing (cutting, deleting, editing new polygons with attributes) works fine. I am saving the changes after every edit or so ...
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0answers
212 views

Changing unit of area from unknown unit to square meters

I am using QGIS 1.8 and I have this polygon. I want to know the area of this polygon and I have used field calculator and it shows my area as 651692439. Under the general tab, CRS is EPSG:4326 - WGS ...
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2answers
3k views

Make a polygon from intersecting lines in QGIS, using Polygonize or similar?

In QGIS, I want to make polygons from a set of intersecting lines. Looking at the screenshot here, I want chop the purple line (it's a closed line, not a polygon) where it crosses the green and blue ...
2
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2answers
174 views

How can I get repeated vector grid in horizontal direction?

I need to get repeated vector grid layer in horizontally direction. I created many polygon vector grid layers, and their extents as listed bellow (Xmin-Ymin, Xmax-Ymax): Layer 1: 5910000 3040000 ...
3
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1answer
188 views

Obtain Longitude/Latitude Values and Export Data From QGIS

I have a CSV file with address data elements (Street# and Name, City, State, Zip). I'd like to be able obtain corresponding X,Y coordinate for each of the address? How do I achieve this using QGIS? ...
8
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2answers
1k views

How to split lines into equal segments with QGIS?

I'm attempting to split a curved (wiggle) line into equal length segments. Have used Grass's v.split which works to a degree but does not provide the output I'm after. v.split will extract segmented ...
1
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1answer
542 views

How can I style many layers of vector grid once in QGIS?

After I created many of vector grid layers, I now need to style them in a batch system. Is there any way to do this? If that is not possible, how can I use the layer duplicate option to inherit the ...
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2answers
312 views

How can I change vector grid extents in QGIS?

I created many vector grids, but later I discovered that I need to modify some of their extents, hence, How can I change vector grid's extents (xmin, xmax, ymin and ymax) in QGIS?
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2answers
48 views

Editting Attribute properties in QGIS

I am trying to edit the precision of my area attribute in QGIS 2.0. It is currently at 0 but I want to change it to 3. I have not been able to find the answer to this anywhere. Is there a way to edit ...
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1answer
635 views

Flow Mapping Lines by Magnitude

I am attempting to map the flow of remittances into Japan using the FlowMapper plugin in QGIS. When I use the Style--> Advanced--> Size Scale field--> magnitude command, the lines become so thick and ...
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2answers
2k views

How to interpolate a point vector layer inside a boundary (polygon layer) QGIS/GRASS/SAGA?

I have a to create a heatmap of water temperatures inside a lake for which I have sample points. The map should look much like the climate maps generated by climate change models. I have the ...
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1answer
504 views

How can i clip vector layer in qgis and python?

I want to write a python function to create a shape file layer from clipping an input layer using a mask. Does someone know the way how to do it?
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1answer
47 views

Can't generate leaders with EasyCustomLabeling

I'm using EasyCustomLabeling with QGIS 2.0.1 and can't get it to generate the leader lines it is supposed to in Action 2. I create a new layer with EasyCustomLabeling, move labels to new locations, ...
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1answer
122 views

How to hide grid's labels when zooming out?

I have used polygon grid layer on my map, and I used to label the layer with ID automatically, and the result was convenient for me: But when I zoomed out, the labels didn't hide at all! and they ...
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0answers
498 views

How to add an offset to a GeoJSON layer in Leaflet?

Using the example GeoJSON tutorial code at leafletjs.com. Change the myLines variable so that the two lines overlap, but run in opposite directions as follows: var myLines = [{ "type": "...
3
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2answers
2k views

How do I define a bounding box within a WFS-request?

I need to get some data from via a WFS connection but due to the sheer size of the data, it takes for ever to load into Qgis or MapInfo. MapInfo has a feature which allows you to restrict the wfs ...
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1answer
216 views

no output file with grass:r.los

i'm using qgis 2.0 and i want to calculate a viewshed using r.los from grass tool box. after typing in the python console and a few seconds, i don't get an error message, but there is no file. the r....
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2answers
53 views

Fast location of items via attribute table in QGIS

Is there a way to quickly go straight to an item via the attribute table in QGIS 2.0.1? E.g similar to in ArcMap when you have the table open and double click the record and it zooms to it? I have a ...
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0answers
15 views

Eliminating/minimizing distortion in 200 NM EEZ buffers [duplicate]

I frequently need to calculate buffers of 200 nautical miles from country or baseline polygons in order to map maritime Exclusive Economic Zones (EEZs). However, I've noticed that when generating the ...
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0answers
32 views

Problems with other applications after installing QGIS 2.0.1

Since the official QGIS installation 2.0.1 (Virtual Server) various core applications from other departments in the municipality do not work always properly. Does anyone know the problem? Thank you ...
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0answers
38 views

Viewer Function

Is there a Viewer function/display in QGis as it is in ArcGIS. Or is there an other possibility to limit the access (just visualisation, no analysis). Thank you for your answer.
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3answers
1k views

Is there a way to hillshade vector polygons with a DEM in QGIS?

I have a layer of cadastral polygons that I'd like to display as hillshaded. For the elevation model I can use either an SRTM geotiff or use a set of 20m contour vectors. While I could make a jpeg ...
3
votes
1answer
316 views

how to snap two line vertex in two different layers used in QGIS

I want to snap between two poly-lines from 2 different layers (Layer1 in Brown and Layer 2(postGIS layer) in Pink color- ), but my snap option don't work. I have changed the tolerance to different ...
0
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1answer
286 views

Extract layer attributes and addresses QGIS

I have congressional district layer and a csv file with addresses. I'd like to extract all addresses and their corresponding congressional district. How do I do that using Qgis? The CSV File contains ...
5
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1answer
84 views

Contacting developer of QGIS plugin?

I want to give feedback to the developer of a non-core QGIS plugin. (Numerical Vertex Edit by Cedric Moeri, who seems to have no webpage for his plugins) I joined OSGeo Wiki but hardly know my way ...
2
votes
1answer
246 views

How to randomly select from existing points within each polygon?

I have a polygon layer (where each feature has a class attribute), and a point layer, and there are at least 10 points within each feature of the polygon. Is there a way to randomly select only "k" ...
3
votes
1answer
306 views

Why does Save as “Rendered Image” change the raster styling?

Rasters exported from QGIS (via Save As > Rendered Image) do not retain original styling. See attached. Any thought on how to prevent this error? The top image is exported from QGIS as a .bmp, the ...
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0answers
1k views

Indoor mapping with floor plans and item(s) to track

Warning: GIS noob here. Essentially I want to be able to create a floor plan for a given room. Consider the following image of a floor plan in image format: I would have the measurements of every ...
4
votes
2answers
5k views

QGIS Get extent of layer

Is there a way to get the extent (bbox) of a vector layer in QGIS? I see that I can update the extent, but I am looking for the actually for coordinates of the extent.
2
votes
2answers
288 views

Minimum requirements (especially screen size) for QGIs - Android

I would like to try Qgis on Android devices, but before, I would like to know the minimum terminals requirements, and especially the screen size or resolution, what is the minimum screen size do you ...
0
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1answer
151 views

Analysing a network distance to two or more points using GRASS or QGIS

I am doing a piece of analysis work looking at distances along a network in GRASS. Most of the analysis involves finding which parts of the network are within 600m of a series of points. GRASS does ...
1
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2answers
83 views

View an .ecw-file in QGIS 1.8.0? [duplicate]

I have got a .ecw-file that I want to somehow import into QGIS 1.8.0. Is there a plugin that I can install that can help me do this or is there another way? The .ecw-file contains rasterdata.
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1answer
225 views

Installing updates/patches for bug fixes in QGIS?

I'm trying to fix this bug in QGIS 2.0. I suppose the code, under the "Files Changed' tab needs to be copied/installed somewhere? Could you please advise on how to do so? I cannot find any help ...
2
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4answers
159 views

Best way to 'join' polygons

I'm looking for the best ways to 'group' a budge of block polygons in a new polygon that should be the town. My block layer is something like this: Or zoomed: And I'm looking to get something ...
2
votes
3answers
376 views

Imported GPX files into QGIS ver 2.0.1-fields missing?

Just imported GPX file into QGIS.Opened attribute table. where are the following fields? Latitude,Longitude,,symbol,and time . Am I missing something??I used a Garmin Oregon 300 to collect the data. ...
0
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1answer
92 views

attribute table in qgis wont save custom values

I am trying to edit a point shapefile in qgis and I have editing on for that layer, I have added a new column for the custom data, I have set it to text and have 8 characters allowed in the column ...
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1answer
291 views

Using Openflights database in QGIS?

I would like to have a shapefile with the airports position and the routes of the planes I've found Openfilghts but I can't use it in QGIS. Seems that the format of the DB .dat is not supported by ...
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2answers
88 views

Show only some buildings

How do I show only some buildings? I only need to show 3 cabins in the forrest, but not every house in the whole village around, and the city close by. Maybe some of the symbol buildings in the city ...
3
votes
1answer
347 views

Show alternating contour lines

Is it possible to show only every other counture line? And how do you do that? (Im new to QGIS Lisboa 1.8.0, but even newer to QGIS Dufour 2.0.1, but have used ArcGIS a bit a while ago, and also ...
0
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1answer
41 views

How can i find shrines nearby location [closed]

How can i find shrines/complex/institute nearby location in qgis and highlight them. The below image is similar to my shape files which contains all information of all attributes,i don't know python, ...