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4

I would do this in two steps. Firstly add a new field to contain the area of your polygons (see below) give it a basic name such as Area and make the type double (see this for more details). You can then calculate the geometry of your polygons in your new field by right clicking the field heading and selecting Calculate Geometry. Which will bring up the ...


4

You can use the Select (Analysis) tool to select a subset of features based on a SQL expression and export the selected results to a new feature class. In this case, I used the following expression: SHAPE_Area > 100 Alternatively, you can perform the same action directly on the attributes using the following workflow: Open attribute table > Select ...


3

In order to solve your problem: Create a FileGeodatabase In the FileGeodatabase create a FeatureDataset Import the shape in the FeatureDataset In the FeatureDataset create a Topology In the wizard choose next and in the Rules page click Add Rule Select "Must Not Overlap" or "Must Not Have Gaps", check "Show Errors" and click OK. Complete the wizard and ...


3

To create Voronoi polygons in QGIS there's a tutorial here use Vector::Geometry Tools::Voronoi Polygons. This produces one polygon per input point; the attributes are copied to the polygons which is important later. Dissolve the Voronoi polygons using the territory attribute from the points to form territories. Vector::Geoprocessing Tools::Dissolve .


3

The problem you are referring at is called "Point in Polygon" - if you google it you'll find various solutions with various tools of various complexity. You can pick up what ever suits you best or create your own solution. A simple C program can be found at stackexcange


3

This is a relatively easy process to perform in MapInfo. There isn't a Spatial Join tool in MapInfo, per se. However, you can do the join using the Update Column tool. Note, I'm using 12.5, but the steps are the same in 10.0. I created a polygon table called Polygon and gave it a field called PolyID. I also created a point table called Point and gave ...


3

From the GDAL page for the Shapefile driver: SHPT_POLYGON shapefiles, reported as layers of type wkbPolygon, but depending on the number of parts of each geometry, the actual type can be either OGRPolygon or OGRMultiPolygon. So the answer to your question is YES ;-)


2

You can download administrative shapefiles from here. Simply select Russia as your Country and Administrative areas as your Subject. You will receive 3 shapefiles of differing administrative levels so you can choose what level you would like. Here is are some attributes for the lowest level: Hope this helps.


2

The thing you are looking at is a sliver geometry. Similar to @sgillies's answer, except use a few buffer parameters to control the chiselled geometry shape: import json from shapely.geometry import shape, JOIN_STYLE eps = 0.001 # epsilon that is approx. the width of slivers, e.g. 1 mm # Load the original polygon from GeoJSON poly = ...


2

How about dilating and eroding by a small factor eps? geom.buffer(eps).buffer(-eps)


2

You don't mention the software you're using, but one quick and dirty method I've used in ArcGIS is to add a scratch polygon layer, draw a simple rectangle polygon in it which covers the interior space you want to preserve in your source polygon (it doesn't need to be a rectangle, and can extend to cover the entire source feature if that's easier). Then use ...


2

This is an easy task for OpenJUMP. Select the "Create Polygon from Closed Area" tool. Click inside the hole and a new polygon that fills the hole is created. Tool works also for filling empty areas between several polygons.


2

If you want to draw features like the one you posted you should use the Arc tool. It is available on the Editing toolbar from the dropdown menu which usually displays Trace. There are a couple of different Arc functions, check them out here. You can also make Bezier curves, which are easier to reshape.


2

This works without SA or 3D import arcpy, traceback, sys ##, numpy from arcpy import env env.overwriteOutput = True pntFile=arcpy.GetParameterAsText(0) rasters=arcpy.GetParameterAsText(1) rasters=rasters.split(';') theFields=arcpy.ListFields(pntFile) theFields=[x.name.lower() for x in theFields] result=arcpy.GetCount_management(pntFile) ...


2

In a similar case, I used a linear feature derived from the polygons on the top, and the polygons feature below. Then, you can symbolize your lines accordingly, whereas the polygons borders (the outline color in ArcMap) can be set to no color.


2

You can use the Dissolve function on a column which contains attributes relating to a specific area. This should combine all separated polygons, such as those of Hawaii, into a single polygon.


1

There's a couple of ways of going about this. In both cases ensure you have set up snapping. Cut your hole (Egypt) as per the tutorial and you will get your original polygon with a hole where you want the new feature to be but note how, in creating the ring, it leaves the original outside edge alone (you need to digitize along the edge in this case ...


1

There is a good tutorial http://www.gdal.org/ogr_apitut.html It's written in 3 languages : C, C++ and python (near the bottom) How to intersect? you get both geometries (OGRgeometry) which you can make from WKT which is easy to write then use OGRGeometry::Intersection to calculate the bit that's inside then cast that to OGRlinestring and call get_length(). ...


1

If I understand you correctly, not in any GIS package I'm aware of. The general procedure here would be to use two polygons and symbolize them separately. That said, it is possible to edit edges of a single polygon separately - that is, move, add, delete vertices, etc. - but symbolize then differently, not as far as I know.


1

There's also a downloadable tool called Curves and Lines, originally developed for preparing data for the parcel fabric, that might do what you want. Takes some time to figure out what tolerances to set the parametes to, so try it on a copy of your data first. This is designed to clean up existing features, not add new ones.


1

This tool should do what you are asking for Smooth Line (Cartography) without having to click and drag.


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This is a two-step procedure with ArcGIS. This method is also suited for automating with ModelBuilder or Python. Eliminate Polygon Part (Data Management). Use this to fill the polygon hole. For this example I specified 50% as the condition in the tool parameters Erase (Analysis). Erase the newly created polygon with the original polygon to get the ...


1

In ArcGIS, in an edit session, use the autocomplete polygon tool to draw a line accross your hole. This will create two polygons with the correct topology, and you can directly merge them (after completion they will be both selected, so you open the edit menu and click on "Merge"). in QGIS, you can use the setting for snapping to do he same task (see this ...


1

You can run the attached python script to fill donut holes and then Union the original features with the filled polygons. From the union you should be able to choose the donut holes by a query of "FID_POlYS" = -1 (substitute the proper field name there). import arcpy import os arcpy.env.overwriteOutput = True def iter_geom(g): for i in ...


1

OK, got it now! Thx for your supply! Just divided the bears_buffer -layer into 4 smaller datasets, ran the intersect tool and loaded the output into excel. Then used the pivot table, worked very fine, but a more simple way would be better. The rest of the data needed, I joined by the spatial join tool.


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You have to create a new shapefile of type polygon. The points layer can only contain points. If you set snapping on the point layer, the vertices of the polygon will exactly hit your points.


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In QGis, use the "convex hull" tool from the vector submenu. From the points shown this creates the following polygons:


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Note: Edited answer based on additional info provided by OP Try the following: 1) Combine the county and hospitals datasets, either via a spatial join or with identify (I personally prefer identify so I have a new layer to work with, but either should work). This should give you a single point dataset with all your hospital info, but with the addition of ...


1

instead of null fill, use a completely transparent fill, like this reference: https://twitter.com/derekswingley/status/487335272825094144


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Try: polygone1 <- gBuffer(polygone1, byid=TRUE, width=0) polygone2 <- gBuffer(polygone2, byid=TRUE, width=0) clip2 <- gIntersection(Polygone1, Polygone2, byid=TRUE) It is ugly, but it usually solves this kind of problem. HTH



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