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2

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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There's also this jsfiddle I stumbled upon. I can't claim it as my own but you can sort through the options objects via event.target.options or even set the color attribute for a target event via event.target.setAttribute()


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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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My qgis plugin/python module allows you to simplify geometries by "contract" (shrink only) or expansion only: https://github.com/albertferras/simplipy https://plugins.qgis.org/plugins/simplipy/


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The Intersect tool, when run on polygon input(s), and requesting LINE output, will produce the result that you are after i.e. the lines in common to neighboring polygons. This is is described in the ArcGIS Help about how Intersect works. As noted by @klewis the lines that result are "duplicated" but this is easily addressed by running Dissolve on that ...


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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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I am sure more elegant ways to perform this task, but I have come to a solution. This requires sp, ggplot2, and rgeos. As before, I attached the file with the point information. PlaceCoord <- SpatialPointsDataFrame(data.frame(UTM.Easting,UTM.Northing),data=data.frame(PlaceID,Name,lngYear,IDgroup),proj4string=CRS("+init=epsg:32717")) #Establish the ...


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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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I ended up calculating the center point of each polygon from the SW point in the dataset by moving the point 45 degrees NE, 1.41 * side length, based on area given. Then I used the answer given in: Creating square buffer around point feature using ArcGIS for Desktop. That worked great. Alternatively I am trying the Python code that is also linked in the ...


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You could try converting the raster to a polyline (http://pro.arcgis.com/en/pro-app/tool-reference/conversion/raster-to-polyline.htm) and, subsequently, converting the lines to polygons (http://pro.arcgis.com/en/pro-app/tool-reference/data-management/feature-to-polygon.htm). The feature to polygon tool requires an advanced license; if you don't have an ...


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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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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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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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Well I finally made it using array_agg() function after st_dumppoints(): SELECT a.id, st_distance(a.points[1],a.points[2]) FROM( SELECT c.id,array_agg((points).geom) as points FROM (select id, ST_DumpPoints(the_geom) as points from my_polygon_layer) as c where (points).path[2] = 1 OR (points).path[2] =3 group by c.id I don't know if there is a more ...


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You can follow this guide to merge polygons using the toggle edit and then merge selected buttons. Make sure the "Advanced Digitizing" toolbar is on - Right-click on any toolbar and you will see a list of available toolbars or use the menus and goto View > Toolbars These are the basic steps: - Right-click the layer and choose "Toggle Editing" - Select ...


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The answer is defining the bigger buffers as disks (outside buffers around and outside the small inner ones that does not include the inside area of inner buffers), each bigger buffer will have specific inner ones and the overlaps of bigger buffers is not important. So, easily we must follow the process of buffer making from small ones to bigger ones.


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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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Solution that works if your small polygons do not overlap: arcpy.Union_analysis("small #;large #","C:/FELIX_DATA/SCRARCH/SCRATCH.gdb/UNION","ALL","#","GAPS") arcpy.SelectLayerByAttribute_management("UNION","NEW_SELECTION",""""Name" = "Name_1"""") arcpy.DeleteFeatures_management("UNION") arcpy.Dissolve_management("UNION","C:/FELIX_DATA/SCRARCH/SCRATCH.gdb/...


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1) In Geoprocessing, use the Union tool to create a single feature class. This causes a "cookie-cutter" effect on overlapping polygons. 2) Start editing on the newly created feature class, exported from the Union. 3) Delete the desired polygons.


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The best tool I tried is "Thematic raster summery" implemented in Hawth tool . The result is a dbf file which is opened in excel. In this file, rows are your polygons and values inside columns represent the number of each pixels for a unique raster gridcode. Good luck.


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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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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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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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Solution below assumes: you are using ArcGIS v. 1.3 you are working from mxd, name of polygon layer is PGONS, it has unique name stored in field PGON_ID and you transferred coordinates of centres into PGONS table and stored in fields as shown below: arcpy.SpatialJoin_analysis("PGONS", "PGONS", "D:/Scratch/SJ.shp", join_operation="JOIN_ONE_TO_MANY", ...


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Have you considered just adding own layers for regions where multiple species occur? For example, if you have the species A which is visualized green, and the species B which is visualized red, just make the regions where both of them occur blue. Might be a bit too simplistic, but it works in my mind.


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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 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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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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