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1

If you mean to have 1-4 adjacent color boxes at bottom-left, top-left, bottom-right, and top-right positions then I would do it by having one square symbol with points POINTS 0 0 0 1 1 1 1 0 0 0 END Then I would make four copies of the symbol with different ANCHORPOINTs as documented in http://www.mapserver.org/mapfile/symbol.html. ...


0

QGIS has ability to connect to GRASS.Follow the below links to integrate GRASS plugin with QGIS.Add GRASS vector data to QGIS and export into shapefile or any other format. https://docs.qgis.org/2.6/en/docs/user_manual/grass_integration/grass_integration.html http://qgis.spatialthoughts.com/2012/01/setting-up-working-grass-environment-in.html


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You may export to Shapefile with v.out.ogr Example from the doc: v.out.ogr input=lines type=line output=lines.shp


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Update: IMHO Shapefiles should be called deprecated these days. GeoPackage is a promising successor. It's similar to Spatialite but from OGC and it's been adopted by many software, inlcuding ArcGIS and OGR. See the official homepage http://www.geopackage.org/ and e.g. this presentation: http://www.slideshare.net/JeffYutzler/geopackage-swg-overview


1

Altough I wasn't able to find a bug in the above code... I managed to work it around using another way to load GeoJSON based layers. Another thing, the lat and longs weren't properly ordered in the example given (so that the correspond to positions on Rosario, Argentina)... Below are written correctly. <!DOCTYPE html> <html> <head> ...


1

Perhaps you could to use coordinate X and Y from the group of point to obtain x min, x max, y min and y max and then you could obtain X and Y from the center and the radius or diameter. Obviously, you'll obtain 2 data, X and Y, you should to choose the more interesting from your work, mínimun, mean, maximum... In this way to obtain the circle and the ...


1

Thats what you need to add: import sys # where is the module sys.path.append("/Applications/QGIS.app/Contents/Resources/python/") sys.path.append('/Applications/QGIS.app/Contents/Resources/python/plugins') qpp = QgsApplication([], True) QgsApplication.setPrefixPath(r"/Applications/QGIS.app/Contents/PlugIns", True) QgsApplication.initQgis()


0

Your city coordinates are likely to be in WGS84 EPSG:4326. But the DEM grid is not, and Set CRS for Layer is the wrong tool to change the CRS. Use Save As ... to a different filename and CRS. But you first have to now which CRS the DEM data is actually in. If you can't ask the data provider of the DEM about the source projection, take the data from ...


1

I would put the data in a database (PostGIS) and extract the data to QGIS with a (probably materialized) view.


6

If you only need these fields inside QGIS, you can use virtual fields. These allow using an expression (like $length) that depends on other values or the geometry. Open the field calculator, add a new field with the name length, check the "Virtual Field" checkbox and enter $length as expression (or something else for the other fields). These will however ...


7

Interesting question! I'm not aware of any other way of achieving what you want, but using PyQGIS. Read the code below. It has some texts in it: 'lines', 'length', 'startX', 'startY', 'endX', 'endY'. You can adjust those names in the script for it to work on your data. The first one is you layer name, whereas the rest corresponds to field names. I assume ...


2

Definitely, you need a "Group stats" plugin: a litle tutorial from Anita Graser: https://anitagraser.com/2013/02/02/group-stats-tutorial/ It works like a dynamic table in Excel.


1

The geojson layer is in EPSG:4326, not 3857. For the center_coord, you should reproject the degree values to EPSG:900913: new OpenLayers.LonLat(lon, lat).transform(new OpenLayers.Projection("EPSG:4326"), map.getProjectionObject());


0

This looks like a projection issue. Your GeoJSON is showing units in degrees longitude and latitude: {"type":"MultiPoint", "coordinates":[[-33.015055,-60.655964],[-32.940781,-60.636731],[-32.917201,-60.683852]] }; The default GeoJSON CRS is a geographic coordinate reference system, using the WGS84 datum, and with longitude and latitude units of ...


0

I would enclose the area in the above picture. In other words make a single polygon surrounding the points. Determine the area of the polygon. Then get a total point count within the area (all colors combined) I would then get a point count for each of the separate colors within that area. Find the percentages of each of the colors from the total point ...


2

If the points are regular points having the same distance between each point, you can convert the points to raster instead of polygons. But you need to select the proper cell size, simply by measuring the distance among the points. Then you can Go Raster -> Conversion -> Rasterize. Set a vector layer to process, a field with values and desired raster ...


1

If they are in the same projection You can use spatial join from Vector -> Data Management Tool -> Join Attributes by location. Try to use "Take attributes of first located feature" as shown below.



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