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5

There is no way to define "outside only" in gBuffer. You have to go through the additional step of turning the inner polygon to null, and for a good reason. You can use the raster::erase function to remove the internal polygon. If you really want this as part of the gBuffer function why not just write your own modification of gBuffer that adds an "outside ...


4

Try this app online svgnest.com/ steps: 1. svg creates a file (as in Figure 1); 2. Go to the link and upload svg; 3. Select with the mouse the container polygon; 4. start after a number of iterations, you can lock and download the svg file (see Figure 2) NB: polygon and circles must be in the same file svg


3

You can use simplify geometries in QGIS vector > Geometry Tools > Simplify Geometries the higher the tolerance value the greater the simplification


3

Make sure that you are using an EPSG code of http://www.opengis.net/gml/srs/epsg.xml#4326 instead of epsg:4326 so that the X/Y lat/Lon mapping is fixed rather than variable as it is with epsg:4326. Then make sure you are encoding the geometries that you send in the same order as you have told GeoServer to expect them. See the GeoServer documentation for a ...


3

You can do this with both the Create Fishnet tool or the Grid Index Features tool. Create Fishnet is a bit more configurable, and can output either polygon or polyline. Both will allow you to set a width and height.


3

What defines which projection is a polygon based upon, and therefore which projection should apply to it? For these vertices, are the right polygons the left or the right ones? That depends on what purpose the polygons are going to used for. If their areas matter, then you should build them in an equal area projection like Albers. If 90 degree ...


3

From the doc: ST_PointOnSurface — Returns a POINT guaranteed to lie on the surface.


2

As you've noticed Google Earth doesn't tessellate polygons. This means that you will need to tessellate your polygon on your own. You could use something like Triangle to do this: http://www.cs.cmu.edu/~quake/triangle.html Here is a list of libraries which will allow you to do this. Some of them might or might not have a program to do this: ...


2

Demo solution with OpenJUMP Original polygons Buffer the polygons so much that they overlap and make a union. This can be done as a single operation with OpenJUMP. Flat end cap and mitre join with quite a high limit are good settings. The gaps between the polygons have disappeared but the union is too large. Use negative buffer for the union and ...


2

Interesting problem! I've done a similar thing with irregular polygons (in this case, buildings were packed so as not to overlap) Used postgresql and postgis, and python. Rough algorithm was Find random point in polygon's bounding box (ST_Envelope) If point outside polygon, go back one step Make a geometry for the tree centred this random point If that ...


2

This is because a hole should always belong to a non-hole - i.e. you cannot have a Polygons where the only ring is a hole. Note that the hole argument is not ignored by Polygon(), it is overridden and the coordinate order reversed by ?Polygons() - "In Polygons, if all of the member Polygon objects are holes, the largest by area will be converted to island ...


2

If there are only two polygons you can do it rather easily by selecting first the both polygons with the selection tool and then deselecting the outer polygon. Two polygons Both selected, press Ctrl-button down for deselecting the outer polygon Result: only the inner polygon stays selected. It would make working easier if the selection color could ...


2

Sorry I didn't realize the errors were in your image. The approaches that you have tried are correct, you just have an issue with the data. Try removing the m-values from whichever dataset is m-aware. While you're going through this process, I'd make the outputs the same projection/crs just to be safe. I always feel more comfortable with these types of ...


2

A newer version of ArcGIS solves the overlapping zones problem: https://blogs.esri.com/esri/arcgis/2013/11/26/new-spatial-analyst-supplemental-tools-v1-3/


1

You could use a subquery and ST_Union select ST_AsTexT(ST_Union(a.singlegeom, b.singlegeom )) from ( SELECT ST_COLLECT (ST_Simplify(geom ,. 005)) AS singlegeom FROM PUBLIC .mzones WHERE ID = ALL (ARRAY [ 'GMZ730' ]) ) a, ( SELECT ST_COLLECT (ST_Simplify(geom ,. 005)) AS singlegeom FROM counties WHERE fips IN ...


1

Check if the shapefile's spatial index is stale or corrupt. Based on this technical article from ESRI, the shapefile's spatial index maybe corrupted. The technical article offers a solution that may help you solve the problem. Please have a look at it. Another option is to try to export your data to a new shapefile, and see if that solve your problem.


1

I will also recommend a free tools developed by Jenness Enterprises It is just in case you need to use other shapes or point grids.


1

Step 1: Make a Selection of the specific sub-polygon Step 2: Save your selection as a separate feature, but make sure to choose GeoJSON as your file save type


1

Just to add to @ShahzadBacha's great answer, you can also use: SimpliPy (Plugins > Manage and Install Plugins...) PolygonSimplifier (Plugins > Manage and Install Plugins...) v.generalize (Processing Toolbox > GRASS Commands > Vector (v.*) > v.generalize) And if you're feeling brave, you can: Convert your polygons to lines (Vector > ...


1

Finally I complete my solution. I haven't tested yet in my application but it seems to work in pgAdmin. In my case I have each geometry in disctint tables. What I did was : For lines -> ST_LineInterpolatePoint() with 0.5 factor. For polygons -> I test if ST_Centroid() is inside its geometry. If yes, then ST_Centroid() is the best choice, if not I choose ...


1

Tree grates are circular or semicircular metal things that replace sidewalk right? If you have the locations as points you could 1) buffer the points using the radius of the grate 2) and then use the Erase tool (Advanced ARcGIS license) to remove the grates from the sidewalks. If you don't have an advanced license you can use the Union tool with the option ...


1

This Esri whitepaper might get you started on the path to your answer: http://www.esri.com/library/whitepapers/pdfs/multipatch-geometry-type.pdf Or if you want Delaunay triangulation, you can try out this tool: http://www.arcgis.com/home/item.html?id=6e9bc6cbf93d4939b2eb04ff8519be47


1

You can do this using the Network Analyst Extension. Build a network using your road layer (requires network analyst extension) Identify nearest polygon using point distance tool or near tool (or use existing point if known) Add nearest polygon point and postcode point as stops in the network solver then compute a route distance from your post code point ...


1

I found that using "isMultipart" returned any features that had more than 1 feature part AND any features that had donut holes. I created this script that will instead loop over the features, check the the number of actual objects, then select all features that have 2 or more geometry objects via SelectLayerByAttribute_management. import arcview, arcpy ...


1

Also, an easy way is to use Reclassify tool where you should click the button Classify and change the number of classes to 1. Click Ok. Now, the output raster can be easily converted using Raster to Polygon conversion Tool. ;)



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