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2

Three other possibilities: Project/Save as image, you'll get a georeferenced image of canvas (limited/screen resolution) In Print composer Composer/Export as image, you will get az image of the set page size, no georeference From the command line use --snapshot switch, huge image can be created with georeference (qgis exit after creating the image, can be ...


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You can use this R script You will need these packages: library(rgdal) library (raster) For example for a map called "Prodes1": Prodes1<-readOGR(dsn="E:/PRODES/PDigital2014_22768_shp", layer="PDigital2014_22768__pol", dropNULLGeometries=TRUE) Prodes1$Grd_ranks<-rank(Prodes1$mainclass) #Creating a numeric column for rasterize i<-1 ...


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To download vector tiles you need to be requesting a source, not a style, and the extension is .vector.pbf For example you can download a vector tile for mapbox streets at http://a.tiles.mapbox.com/v4/mapbox.mapbox-streets-v6/1/1/1.vector.pbf?access_token=token


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Well i want did the same but, i canĀ“t find... this the way i solve it. Maybe can help to anybody from qgis.core import * import qgis.utils canvas = qgis.utils.iface.mapCanvas(); layer = canvas.layer(1) maxArea = 0 maxId = 0 selection =[] uniquevalues = []; dP= layer.dataProvider() id = dP.fields().indexFromName('myColumn') #i have the unique values from ...


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I imported my raster file to PostGIS and I used this function to make vectorization of my raster. I used this query SELECT (ST_DumpAsPolygons(rast)).geom,(ST_DumpAsPolygons(rast)).val from my_raster


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You can download a Canada shapefile from DIVA-GIS and selecting the Administrative areas as the subject. You will receive 4 shapefiles of differing levels: Can_adm0 Can_adm1 Can_adm2 Can_adm3 (this is probably the one you want) When loaded into QGIS, you will see Canada broken up into different districts (or wards, zones, etc.). You can run a query to ...


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the pixels that fall within the polygon, and get the sum of the pixel value CREATE TABLE gtur_srtm_inter AS SELECT id, (gv).geom AS the_geom, (gv).val FROM (SELECT id, ST_Intersection(rast, the_geom) AS gv FROM srtm_tiled, gtru_poly_vect WHERE ST_Intersects(rast, the_geom) ) foo; The values ...


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The solution that comes to mind is to use a join between your shapefile and the textfile. Its described on this tutorial. If the attributes values change often, you could use a database backend for your data. QGIS works especially well with PostgreSQL-Postgis databases.


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I am not sure you can find a set of layers as you want but, the commands below generate them: Download world borders from http://thematicmapping.org/downloads/TM_WORLD_BORDERS-0.3.zip or from the Global Administrative Areas (http://www.gadm.org/version2). Unzip the file. Run the following commands in your terminal: $ ogr2ogr -where "REGION = 2" africa.shp ...


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I'd recommend Natural Earth for this sort of data. It comes as shapefiles which can be read by any GIS system (e.g. QGIS) Each country's record has a lot of associated data, this includes which continent it's in, so for example you could colourize each country by continent. You can also split layers out by field value, using a plugin. That'll give you your ...


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There are some options. With Fusion there is the command line ClipData and its switch biaselev:#: biaselev:# Add an elevation offset to every LIDAR point: # can be + or -. The command line syntax for shifting the z values down 90 ft: \ClipData /biaselev:-90 InputSpecifier SampleFile [MinX MinY MaxX MaxY] Another option is the las2las tool wit the ...


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Here is the code without error QgsVectorFileWriter * writer; writer = new QgsVectorFileWriter("/tmp/myshapes.shp", "CP1250", MyQgsFields, QGis::WKBPoint, mpMapCanvas->mQgsCoordinate, ...


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If you review the API (http://qgis.org/api/classQgsVectorFileWriter.html) for QgsVectorFileWriter, the constructor looks like: QgsVectorFileWriter::QgsVectorFileWriter ( const QString & vectorFileName, const QString & fileEncoding, const QgsFields & fields, QGis::WkbType geometryType, const ...


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In addition to the roundness formula outlined by radouxju in his response and others like the ratio of the area of the polygon to the area of its minimum bounding circle - ST_Area(geom)/(ST_Area(ST_MinimumBoundingCircle(geom)) as rnd_check in PostGIS: I find it often helps to check the number of vertices/points in a 'suspicious' geometry - ST_NPoints(geom) ...


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If you want to use QGIS you can use the Points to Path tool. In recent versions (like 2.8 onwards) it's available in the Processing Toolbox under QGIS geoalgorithms - Vector Creation Tools - Points to path. For input, the tool requires two attributes - a group field that specifies the name of the feature that the points belong to (i.e. that will represent ...


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Please check this How to convert points to lines? If you are looking for a different scenario,could you please illustrate it.


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There should be some color progression options that can suit your needs for vector data. Look under "categories and then once you have your value field selected, click the "color ramp" and scroll through. Some of the choices are actually color progressions between two colors. If those aren't quite what you are looking for there go down to "quantities" and ...


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Try Points to Lines. It's an ArcScripts that works with ArcGIS Desktop. I have never tried it myself, but it seems like a good option. There's also the Points To Line tool in Data Management.


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Let me suggest to use the nice vector network analysis tool which you can find in the menu (manual page). It allows you to snap the points to the network (second icon under "Points for analysis") automatically and is really easy to use. Two screenshots generated based on your data (I created a LatLong location, epsg:4326 for it). Travelling salesman in ...


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Change the style of the vector and make the border the same colour, possibly a bit thicker too. That should mask it. I'm guessing that it isn't a real gap.


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First of all, you are using a Polygon symbolizer (for vector data) on a GeoTiff (raster data), which won't work. On the raster data, if it is a single channel raster, you GeoTiff will have a value that represents NoData (usually a very large negative value like -9999 - QGIS can tell you what it is). From your pictures, I believe you want NoData to appear ...



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