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Similar question here. I have a multipart polygon (one forest divided in multiple separate plots). I want to assign one number to each part. And a way to find out how many parts are. Reason is I have to draw a map of each of plot separately. Thank you for an answer by using QGIS!


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Something about the configured R scripts folder seems off. Do you remember changing anything related to that. It's probably best to open a ticket for this issue.


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UPDATE: I think I've resolved this! The key is in symbolizing my lines of bearing as overlapping polar Vector Field markers. I symbolized my lines of bearing as points from a text-delimited layer, then turned the points into lines by changing the symbol layer type to a Vector Field marker. I set the the Vector type to polar, which allowed me to set my ...


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in the past when I disabled my plugins, the minidump error message didn't go away But when I just moved (or cleared) the contents of the plugin folder, that is C:\Users\Rob.qgis2\python\plugins, the minidump error stopped then I just re-installed my plugins one by one. I have also done this to improve QGIS loading speed. Eventually too many or a particular ...


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The process is called "geocoding" and you can use the MMQGIS plugin for it. You can find detailed documentation at http://michaelminn.com/linux/mmqgis/


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I have just found out the reason of the python error message. I used an "ö" in my username in Windows which causes the trouble. I renamed my windows username and had to rename my user folder (thought we have the year 2015 and "ä,ö,ü" wouldn't cause trouble like this anymore!) but now it works again.


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(Posted this as an answer as it's too long for a comment. But atleast I can add an image!) I think you may need to install the rpy extension for Python as mentioned in this post: Resources on using R in QGIS for R users?. You should be able to install this extension using the OSGeo4W setup and selecting Advanced Install setting. Go through the options ...


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According to this ticket: https://trac.osgeo.org/gdal/ticket/3404 the tilted perspective projection is not added to GDAL (but is in Proj.4). That is why GDAL/OGR based programmes like ogr2ogr, gdalsrsinfo and QGIS can not understand it, while cs2cs (based on pure Proj.4) and the testing suite of QGIS can work with it.


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Here is a solution for whose want to create specific svg file depending on the feature data Language c++ / QT4.8.5, qgis api c++ 2.8.2 A svg file contains xml code In this exemple we put a specific color and change the use based on the 'vitesse' parameter of the feature This sample code draw 3 differents arrows : small medium and large ina 30x30 pixels ...


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You can do this and more prior to importing into QGIS with a tool called GPS Track Editor (www.gpstrackeditor.com) It allows you to merge (from simultaneously running gps units), restructure, increase frequency (densify), reverse and filter for local inconsitances. A great free utility.


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So I solved it. It wasn't that hard. I open csv as "delimitedText" layer. Then I save this layer as "ESRI Shapefile". There is a trick. It fails to save, but it creates a .dbf file. Then I load it back as "ogr" file. pos_csv = QgsVectorLayer("file:///"+folder_name+'/pos_file.csv',"Layer Name","delimitedtext") QgsVectorFileWriter.writeAsVectorFormat(pos_csv, ...


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The original paper describing the Robinson projection included a table of values at every 5 degrees along the equator and the central longitude. Those values are used to interpolate intermediate coordinates This same table is what Esri is using. The PROJ.4 code has a much expanded table with each 5 degree value having an additional 3 values (possibly ...


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As far as I know, the QgsExpression class allows you to select features from a layer that match a WHERE clause, i.e., the expression is a conditional that returns True or False (or unknown) for each feature. If the expression evaluates to True for a particular feature, that feature is selected in the map. What I see from your PostGIS SQL expression is that ...


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I found a solution for my problem. instead of created a layer with a lot of feature, i create a lot of layer with only one feature the algorythm is : create a layer with a indexed name like TRACKS01 add the point with default setting change the attribute value update the layer I make a test with 10 layers, when i start my simulator, all layer move, ...


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This won't be a complete answer as I finally searched the help of a professional to produce the gores with another software. Nonetheless, let me share with you what I (with the help of the links mentioned above and esp. from Hans van der Maarel) found out, in case it is of use to someone: The right projection is in QGis is "Sphere_Polyconic, EPSG:53021". It ...


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That seems like a AutoCAD specific rule, the Shapefile format knows no such definitions. You could try to split up the "garbage" into readable values and then use data-defined text styling based on it.


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While Joseph is correct about the syntax of the CASE statement, your Python issue stems from string quoting. You can use either ' or " to quote strings, and you don't have to escape the other character if used, but you do have to escape the same character. Or you can triple quote (ie ''') which will also allow multi line quotes. In other words: # this ...


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You need to add end to close of your case statement. The following should work: case when "Municipio" is NULL then 'PENICHE' end Tip: What I normally do is to make an expression in the field calculator from the GUI before adding it to the python console. This way, it tells you immediately if your formula will work or not instead of running it though ...


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It looks like the output is always created as a shapefile by default. Some tools don't allow all data types that QGIS normally supports. In the Contours dialogue, you can set the format manually according to http://www.gdal.org/gdal_contour.html by selecting the pencil icon: gdal_contour -f "DXF" -a ELEV -i 100.0 D:/Karten/SRTM/N51E007.hgt ...


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Maybe is not the fastest way but you could achieve this in three steps: Convert your points to raster: Raster -> Conversion -> Rasterize Reduce the resolution: Raster -> Conversion -> Translate (Outsize) Convert your resized raster back to points again using the SAGA pluguin. Algorithm -> Grid values to points. However, I'm still not sure about what you ...


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I found the tool I was looking for! It can be done using the plugin called "Clipper".


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I had the same problem. I think Johann Hurter has the best solution. In my case, for I don't know what reason, when I opened my shapefile it was not in its original CRS (previous manipulation error maybe). Because I activated the projection on the fly it was displaying it correctly on the background map. But when I was trying to clip with another layer it ...


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I suggest using raster based analysis with r.walk in GRASS GIS. An example on North Carolina sample dataset: g.region raster=elevation@PERMANENT v.to.rast -d input=streets_wake@PERMANENT output=streets_wake use=val r.mapcalc "friction = if (isnull(streets_wake), 100000, 0)" r.walk -k elevation=elevation@PERMANENT friction=friction output=walk_cost ...


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It appears that pstoedit is your best bet: http://www.pstoedit.net/pstoedit/ Based on similar question: How to Import SVG into GIS?


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This is known as 'concording' (well, I thought it was, but I can't Google it, so it might not be). Basically, it's a very difficult thing to do. It's unfortunate that the ABS change their boundaries every census, and the 'mesh blocks' were intended to stop this, I think, but even they change a bit. Essentially, what you'd need to do is split up your FIRST ...


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Yes - what you're after is called a "virtual field". Open the layer properties and switch to the "fields" tab. Then, click the "field calculator" toolbar icon. Check the "Create virtual field" checkbox, and make sure you choose an appropriate name and field type for your virtual field. Then, enter the associated expression - eg "Liters" / 3 Click OK, and ...


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Github pages With Github, create a username.github.io repository. Then, for your other repositories, you can create a gh-pages branch. If you have an index.html, you'll be able to navigate to http://username.github.io/project-name to see your map live on the web. Github has information on doing this here. I did this last night, with a quick export from ...


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Google Drive works for me: Make sure that the folder is shared with the public Access the website via www.googledrive.com/host/[id-of-the-folder], e.g. http://www.googledrive.com/host/0Bwc-5JFVTnfIWUlXSklaQndTNGc My folder actually contains two projects/html files. The second one is ...


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Here's an example of how you can do this, using postgresql and qgis. It finds the closest 5 polygons to each polygon in the dataset. The screenshot should show how it establishes distances. Note that I'm using British National Grid (27700) - this a local UTM projection in meters, so over these relatively short distances the results will be quite ...


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Free, simple. Choose one. Not free, but $1/month: http://www.nosupportlinuxhosting.com/ Free but can be a bit of a pain to setup: GitHub You load your folder as a GIT Repository, and using RawGit.com you can display HTML files. Example: Git Repo: https://github.com/HeikkiVesanto/QGIS_Multi_Ring_Buffer/tree/master/help Link to the HTML file in RawGit: ...


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You can also use the "Copy_Coords" plugin (add it in plugin manager).


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In QGIS styling is layer based, so it is generally not possible to set different styles or different symbols for individual features. I think this is because features are handled by the data source, while styling is organized by QGIS's layer. Nevertheless you can get individual styling based on the feature attributes. This is called a "Data defined ...


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So, we've ended up changing tact and moving to spatialite and seem to have managed to do it with an SQL query, including the geometry field which means I can add it as a new layer: Select Distinct T1.toid As TOID1, Min(T1.Hubdist) As MinDIST, T1.ID, T1.geometry From [Hub Distance] T1 Inner Join (Select T2.toid As TOID2, ...


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First, I'm not sure what kind of axis order that your games uses, but sometimes maths stuff uses X and Y at zero on the top left, and increasing right and down respectively. Note that GIS uses X and Y a 0 at the bottom left, and increasing right and up. I think you should be able to swap the Y coordinates in your georeferencing points and be good to go. ...


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Although it isn't a GIS Tool, this is something you could use Gephi for. Especially if you want it to look like your illustration. Straight lines, no problem. Curves are more challenging. Gephi is for network analysis and plotting. It's typically used for things like social network analysis (e.g. analysing Facebook or Twitter networks) This example shows a ...


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Alex has pretty much covered it (as mkennedy did in a comment) and I've upvoted his answer, but I want to offer slightly different wording/take on the issue. All data you can add to a map has coordinate values. However it doesn't necessarily have what those values represent defined. Is it feet or meters or degrees? What is the origin? These kinds of things ...


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intersects gives the boolean value True, False, intersection gives the geometry If you use the dir function of Python dir(intersection) ['Error', '__class__', '__delattr__', '__dict__', '__doc__', '__format__', '__geo_interface__', '__getattribute__', '__hash__', '__init__', '__module__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', ...


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building on Joseph's answer, you might find it more useful to generate a sortable text field. As this is a text field, any attempt to sort M1,M2..M10,M11,M12 will come out as M1, M10, M11, M12, M2, M3 ... M9 If you use M0001, M0002, M0003 .. .M0012 then you have the uniqueness and can sort too. Just modify Joseph's suggestion to 'M' || ...


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In PostGIS you can use ST_Buffer to add a little margin to one of the polygon layers, then use ST_Intersection to get the curbs polygon. Now the ST_StraightSkeleton may give you what you want (haven't actually tested but it should work).


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You can use grass, tool named v.clean. There, you set rmarea. The threshold parameter will be in unit of theme. All feature which have area less than treshold will be deleted.


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A partial answer using selection (not relation) has been published for this question. Question on gis.stackexchange.com


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Hey moderator that deleted my last post on the same topic, please leave this one up. This is completely relevant because I don't believe the answers above still work and I'm not the only one that's struggling here. Either I'm crazy, or the two bits of code no longer work. I've copied these and tweaked them for my use and for the life of me I can't get a tif ...


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You could use the following expression (note that your column must be a String type): 'M' || $rownum


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From my point of vue, projections are not at all easy to handle in QGIS. After days struggling with the different layers in my project, I think I finally understood how SCR works. I differentiate 3 actions : A1. Project properties > SCR, you can click on the icon where EPSG is written in the bottom right corner This defines the proprieties of the canvas ...


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You could use the Group Stats plugin from Plugins > Manage and Install Plugins. This calculates various data statistics for your attributes such as finding the minimum value in a group. I made an example of attributes from the data you gave: Then from the Group Stats interface, select and drag the toid field from the list into the Rows window; and repeat ...


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Working on QGis version 2.8.2-Wien I mannaged to rasterize a line shapefile using the Treatment > Toolbox > GDAL/OGR > Conversion > Rasterize (vector to raster) script. My GDAL/OGR version is 1.11.2. Parameters input was quite strait-forward and it returned me a GeoTIFF image. You can choose the number of bite, format,... The code is also generated and you ...


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Converting a polygon into a perfect rectangle means the same than closing it inside a minimum bounding rectangle (MBR). There are two sorts of MBRs: an oriented rectangle which has its axes in the same direction as the coordinate system, or truly minimum rectangle which can be rotated. The oriented one is also called as Envelope. Let's begin with two ...


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I recommend the Vector Bender plugin for QGIS. I tried it and it works fine and is user friendly. Depending on amount of pair of points that you define, you can either do: translations: translation from one starting to ending point (1 pair) uniform: translation, scaling and rotation (2 pairs) bending: additional deformation (3 pairs or more) You find a ...


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I would say (not being a developer for QGIS) that the only release to be considered beta would be the master builds of QGIS (ie, nightly). QGIS (long-term release) can be considered static (no new features added) but with cherry-picked patches that are back ported for stability, enhancement and security. QGIS (current release) is mainly different from the ...


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Attach this script: # Import arcpy module import arcpy, traceback, os, sys from arcpy import env env.overwriteOutput = True try: # input folder with shapefiles or rasters inputFolder = arcpy.GetParameterAsText(0) env.workspace = inputFolder # output folder for tiles shapefile outputFolder = arcpy.GetParameterAsText(1) # table name ...



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