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Not sure if this still exists in QGIS 2.4 but I use QGIS 2.2 and there is an option where you can save your selected attributes as another shapefile. It doesn't matter if you toggle the edits, you just select which fields you want to save into the new layer: Layer > Save Selection as Vector File... The alternative would be to duplicate your layer, save ...


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You need to use Vector->GeoprocessingTools->Dissolve and dissolve by an attribute (Dissolve Field) to merge subdivided polygons.


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we must put the type of geometry (polygon), is that true? on which file path you speak ? i don't understand. thanks


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To start with, make a tileindex shapefile of your images with the gdaltindex utility. Edit the shapefile by adding new columns for your metadata like to which layer each image belongs to. Add the shapefile into your project and query it with the identify tool for finding the image metadata.


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You can use alternative GDAL driver "OpenFileGDB" which supports also other projections http://www.gdal.org/drv_openfilegdb.html.


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Sort of depends where you are (which country) on what software and methods are usually used or are standardised on - some councils, state governments and governments have required methods. Also what sort of area are you looking at modelling ? Urban, rural ??? eg for Australia have a read of the www.arr.org.au site. They are in the process of releasing ...


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This functionality is under the "Show all features" Button:


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With QGIS 2.2.0 you can use two plugins: QChainage to get the equally spaced points along the input polyline, and Points2One to assemble these points into a new polyline or polygon


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Arcpy use the Numpy array format (hidden to the users) as PyGGIS that uses the Python GDAL module. provider = raster.dataProvider() # path the original file filePath = str(provider.dataSourceUri()) # open the original file from osgeo import gdal raster_or = gdal.Open(filePath) # create a numpy array numpy_array = dataSet.ReadAsArray() # shape of ...


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One option that may be a bit faster (less clicks) or you could call from a script would be to use ogr2ogr command (using OSGeo4wShell (which comes with installation of QGIS)). ogr2ogr -f "ESRI Shapefile" C:/Temp/Shps C:/Temp/test.gdb If you want to export out a subset you may use the same command above but at the end list out the table name(s) (e.g. ...


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myVectorLayer = QgsVectorLayer("polygon", "mypoly", 'ogr') does not create a valid vector layer, therefore mySymbol1 = QgsSymbolV2.defaultSymbol(myVectorLayer.geometryType()) does not return a valid symbol and causes the error you see. Replace "polygon" with a valid file path.


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Unfortunately, neither me nor Ko (who added all the more advanced pgRouting functions to the plugin) could figure out a way to support exporting the isochrones. You have to go back to writing SQL statements if you need the data.


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File Geodatabase in QGIS 2.4 Note: Use Directory rather than File Once the file geodatbase is loaded save the shapefile


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You can use the Dissolve tool from QGIS: Vector > Geoprocessing Tools > Dissolve


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You can right click with a Mac, hold 'ctrl' and click. Or use two fingers to tap on the touch pad, or plug in a mouse with two buttons. When you do that, you right click your layer (that has selected items) and choose 'save as' then check the box 'save only selected features.'


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The distortion is caused by your selection of target SRS, and the CRS you are using in your QGIS project. As soon as you are using a different CRS in QGIS as the one used to create your the raster (jpg file), you will see this distortion. This normal behaviour. If you're setting the same CRS to the QGIS project, the image shown will resemble your original ...


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Based on the comments, it sounds like @Jakob found an appropriate solution. The polygon layer needs to first be converted to centroid points. This is done using: Vector -> Geometry Tools -> Polygon Centroid and then creating the output point layer. The interpolation may then be performed using one of the various methods available. This post has ...


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This option is not included in QGIS but here is what I do: First classify using desired color ramp. Then go to Settings -> Style Manager -> Color Ramp (shows in figure below): Now you can use 'Snipping Tool' to copy the ramp that you used. For example figure below shows the 'Blues' color ramp copied using snipping tool: Now, in 'Composer Manager', use ...


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I may have a solution for you. If flow in one direction is consistently lower than in the other direction, this would work. I think you have much of the answer included in the question. I would attempt to duplicate the layer and draw the limited flow on top of the greater flow and have them both symbolized by the flow value.


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You can also use the format function of python if you have problems to format the string with %s. Python Format String Syntax Your uri would look something like: uri = "file:///D:/MLB Stadiums/Test_R2/Player_Files/Espinosa_2014.csv? delimiter={delimiter}s&xField={field3}&yField={field4}".format(delimiter=",", ...


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It's having problems with the letter s, because your code specifies that as a delimiter (delimiter=%ss is getting interpreted as "," and "s"). Try delimiter=%s.


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I assume two things causing your described error. Make sure you chose the right in- and output coordinate system. If the input image has a wrong coordinate system the output is adjusted according to these distorted information. Try to distribute your control points over the whole image. Additionally, if they are too close smaller inaccuracies have a larger ...


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Assuming you just want the general orientation of the polygon, rather than a specific segment... try the Minimum Bounding Geometry (Data Management) ArcGIS tool with the RECTANGLE_BY_WIDTH or RECTANGLE_BY_AREA geometry type and the MBG_FIELDS option. The MBG_FIELDS option will add the following fields to the output attribute table: MBG_Width—The ...


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Given the nature of the lines you're trying to create versus the geometry you have, I think it will probably be fastest/simpler to just create new features as in the tutorial you have linked to. Any method that actually converts the polygons to lines will involve splitting the lines at certain points and/or deleting a lot of extra nodes/lines/etc. There is ...


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Use the polygon to lines tool and then remove those parts of the line layer which you don't want to keep.


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You can digitize polygons with common borders using the proper settings in snapping options. I am asumming that you already have a polygon layer where you want to digitize something.Go to settings/snapping options and define the following a) Select the polygon layer and define the mode to vertex and segment b) Define a tolerance of 10 or 15 pixels c) ...


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My solution is to digitize the boundaries one after each other, using a snapping tolerance of 10 pixels to fetch the vertices of the existing polygon. Another option is to use the polygonizer: How to go with...somewhat complex geological maps in QGIS?. It combines lines to polygons in an automated way.


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I think this is rather a packaging problem. The package you mention is from the official python sources. For Windows builds with OSGEO4W, the version number is 3.0.1-1, and it is installed by default. According to this ticket for Ubuntu: https://hub.qgis.org/issues/10099, pyspatialite is now part of python-qgis, so no need to install it separately. Maybe ...


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It's possible in the current development version of QGIS (which will eventually become 2.6 - there's instructions on how to obtain development snapshots here), and a potential workaround is available in 2.4. Both methods are done by checking the "Filter with" checkbox under the table's "item properties" tab, and entering a filter expression. In development ...


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Not currently - there's some outstanding feature requests for this: http://hub.qgis.org/issues/10273 http://hub.qgis.org/issues/8006


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They are still there in 2.4, they've just been renamed and moved slightly. "Feature Filtering" is now "Filter With" and uses the one-line filter from the attribute table. "Feature Sorting" is now just "Sort by" and is just below the file name expression.


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I'm afraid you can not use that projection in QGIS. QGIS is based on GDAL, but that does not know winkel II either. Only Proj knows a projection definition +proj=wink2. But it has no support for the inverse projection. According to this similar question on Winkel tripel: How to reproject a raster to Winkel Tripel projection? the projection can not get ...


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To check the number of points per grid cell from a LIDAR point cloud in GRASS you can use the r.in.xyz module. This module creates a grid from the point cloud using a "method" parameter by which you choose how to aggregate the points when importing. If you choose method=n then the resulting raster will contain a count of points for each cell. By setting ...


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Try this link http://dspatial.sourceforge.net/ I hope that helps. Victor


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To use the GRASS tools directly, you need to first import the data you want to work with into a GRASS database. If you use GRASS algorithms through the Processing toolbox, you can skip this importing step because Processing takes care of all the data conversion. It's therefore much more convenient. You don't have to explain to your students how GRASS works, ...


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Just add another attribute to the vector layer's attribute table and fill it with the value using Field Calculator. For help with the field calculator, please check the docs: http://docs.qgis.org/2.2/en/docs/user_manual/working_with_vector/field_calculator.html Note that QGIS does not support 3D geometries so you have to store your z value in the attribute ...


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The shapefile from Natural Earth contains the south pole. The Mercator projection is not able to render that point for mathematical reasons (it would be in inifinity). What you can do: Set Project CRS from Layer (that would be EPSG:4326) switch to edit mode Delete the bottom line of the antarctic save the layer Change Project CRS to EPSG:3857 If you ...


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If it's acceptable for the entire line for the dead end street to be drawn using a square cap, then you could use QGIS' "data defined symbology" to achieve this. In your line style properties, click the "data defined properties" button. Check the "cap style" option, then click the expression button. Your expression will need to look something like this: ...


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Is it a shapefile your using? If so open the .prj file with any text editor and look for tye word "mercator" if you dont see that but see WGS84 than use ESPG:4326. Going off the screenshot its one of those, as those are really the only two that people make available for download


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Looks like you want a Mercator Projection. Try to save-as your shapefile assigning the WGS 84 / Pseudo Mercator (EPSG: 3857) projection or assign this projection to your project (using transformation on the fly). See also: What is the standard Mercator projection?


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Yes, there is a Flicker group. See also, the Screenshots page on the QGIS.org site for latest samples of maps. Not sure about the Chugach State Park map. Generally, the splash screen map is of a specific area, but not necessarily produced with QGIS.


0

You might like to use Fusion. It is a free software for point cloud processing and visualization . 1- Look into the manual for a command program called Catalog. It returns descriptive statistics from the point cloud. What you want is the Catalog's switch density:area,min,max. The manual description says: Creates an image for all data files that shows ...


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SimpleReports works fine for me. The plugin manager installs it without any issues. You can try downloading it manually and unzipping it into the plugin folder.


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QGIS lines have a join style and a cap style. If I understand you correctly, you are looking for a feature to have different cap styles depending on whether the cap is at a line end which meets another line or if it's a dead end. That is not implemented yet as far as I know.


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Buffer the lines. Use Difference to subtract the buffer polygon from the original polygon (p0).


1

Go for print composer. Increase the page size and resolution. Add the map and if you want to create a map of the whole world, make sure you zoom to full extent. Then save as image. If the size is not big enough, increase the paper size further. A0 with 300dpi should easily be possible if you have enough RAM.


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If you have georeferenced images, you can use Raster -> Miscellaneous -> Build Virtual Raster or Merge to make a single raster from them. The first one does not even create large files. If you have finished adding images, you can still export to geotiff.


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Do not use Set CRS for Layer if you want to reproject your data. It changes only the CRS definition, but does not recalculate any coordinate. So set it back to what it was before (WGS84 I assume), and use Save As ... under a different name and different CRS.


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Your expression should be "taharuu_grass_rst@1" >=0.003 and "taharuu_grass_rst@1"<= 0.5


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Yes. It does as it appears from looking at the source code for the Spatialite Data Provider. The QgsSpatiaLiteFeatureIterator class is the one that supplies the features to the map upon sending a rectangle extent. You can just search for 'spatialIndex' in that class to see they actually use the index if available.



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