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3

The polygon is not "wrong", it's just not representing landmass It uses 1 polygon for each province. You can find polygons representing Canada's borders and land surface on GADM or DIVA-GIS


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If you use the Identify Features button and click on a point where multiple polygons are present, you can right-click the attribute of the polygon underneath from the list and select Toggle feature selection. The polygon should now be selected:


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Here is a...unique(??) way of doing it. I managed to create routes using QGIS 2.14 with GRASS and rasters. I got the idea from here. To summarize we will rasterize the land and sea, run a proximity algorithim, invert the output, run a cost, and drain algorithm in GRASS and finally polygonize the routes to polylines. 1) Rasterize your land and sea. First ...


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Two possibilities. The picture you have there seems like a movement with the correct scale and form already. That can be done by finding the exact displacement and moving it back via the "move" delta x/y from the editor options. Measure the distance and use for example good old pythagoras or some tool to get the delta x/y. The second possibility includes ...


2

As @Midavalo suggested, there is likely a small gap in your lines. Zoom in and see if all the lines are touching. It isn't surprising that this is happening on the edges of the extent of your lines feature class because internal lines would cross each other and close the shapes. But there is likely a gap where the lines don't touch at the edges. You can ...


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CartoDB doesn't currently have polygons for city regions, so if you have the city boundaries available you will have to import the boundaries to your CartoDB account and merge them with your current data. You have two options: to use the Merge Datasets option in CartoDB or to run a SQL query. Let me explain the solution in both of them. If you want to use ...


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To do this I would use the Union tool to calculate the overlap relationships between polygons. I would then use arcpy.da.UpdateCursor to iterate through each polygon and add up the ranks/weights of any polygons that overlap in that area.


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Your model appears to be correct and you are using the %value% correctly, that is the ID of what your are calling your station number. The error message says you have no spatial reference, i.e. either your DEM or Polygon dataset are missing a defined coordinate system. So you need to make sure they have that set. Look into the Define Projection tool. It ...


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In the future please provide information on what you have already tried and a reproducible example. Whereas this Q&A site is a great resource we are not a coding service. The rgeos library provides functions for overlay/intersection analysis. There are important nuances in the type of function (covers, within, contains) that is appropriate here. There ...


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If I understand what you are trying to do, you don't need to dissolve, you just need to summarize by landscape zone after intersecting the two datasets. If you do this in a geodatabase the area of each polygon is calculated when the intersection is completed.


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I would try these steps, Erase the Blue Polygons by the Yellow. Creates extents with Minimum Bounding Geometry (Envelope). Append the Extents to the Yellow.


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You can also use ST_PointN on the exterior ring of your polygon. SELECT ST_Distance(ST_PointN(geom, 1), ST_PointN(geom, 3)) dist FROM ( SELECT ST_ExteriorRing(geom) geom FROM my_polygon_layer ) a;


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Yes, you can. You need to use the Geostatical Analyst's "Areal Interpolation" method in ArcGIS. This will give you a statistically sound "smoothed" / interpolated surface for your data.


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You are missing ST_AsText, as @WKT mentions above. This should work for you: select ST_AsText(geom) from polygon where ST_Intersects(ST_GeographyFromText ('POLYGON((210000 2400000, 300000 2300000, 330000 3708400, 210000 2400000))'), polygon.geom);


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I have created 3 polygons called Deer Lions Bears, and used the Tranparency slider on the colour. the transparent colours show which polygons overlap


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You can convert these points to raster by FeatureToRaster and set cell size to grid width, Then use RasteToPolygon convert raster to grid polygon.


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I would convert the Polygons to Polylines, combine the lines you desire, creating a new closed line. The Construct Polygon tool on Advanced Editing toolbar works nicely to create a Polygon from polylines.


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To import the Shapefile to PostGIS: ogr2ogr -f "PostgreSQL" PG:"host=localhost user=user dbname=db_name password=pw" -nln public.world_borders -nlt MULTIPOLYGON "TM_WORLD_BORDERS-0.3.shp" The Shapefile is imported as MULTIPOLYGON. If you want to expode it to POLYGON in PostGIS, use ST_Dump: SELECT ogc_fid, fips, iso2, iso3, un, name, ...


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I had to face the same errors when trying to import PostGIS geometries into R. I could manage to iterate readWKT() through the polygons with the help of the apply-function-family: All credits to: https://spacetimecereal.com/2015/01/13/loading-postgis-geometries-into-r-without-rgdal-an-approach-without-loops/ Connect to PostgreSQL DB: drv <- dbDriver("...



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