Process of creating geometric polygon features.

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4
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1answer
2k views

Create overlapping polygons from contour lines

Working in ArcGIS 10, I have a set of contour lines representing density of commercial square footage, and I have a set of points representing local maxima for each peak of the dataset. For each ...
2
votes
1answer
37 views

How to generate rectangles considering only a percentage area of a base object?

I am trying to generate a rectangle by considering a small percentage of area of the extent of a geometry object in the PostGIS. I have tried to use the ST_Scale function. It successfully generates a ...
1
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0answers
41 views

Creating voronoi polygons from polygons?

I have a database with buildings and for some further analysis I need to: aggregate adjacent buildings (preferably without losing the height attribute, but I can work my way around that) once I have ...
1
vote
1answer
40 views

Create repeating pattern of raster or polygons in ArcGIS

I want to create a repeating pattern of raster OR polygon features based on an existing sample, so that the sample fills up a larger area in a repeating pattern. For example, with a sample of 10x10 ...
0
votes
1answer
332 views

Polygons not showing in ArcGIS for Desktop?

I am using ArcGIS 10.2. I have used the following procedure to creat polygon: 'Add XY data' to create points 'XY to line' to create line (but I could not see the lines) 'feature to polygon' to ...
0
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0answers
10 views

Set of points to multi polygon with specified distance

Is there any algorithm that can transform set of points to the set of polygons with defined maximum distance between points, especially I wonder if it is possible for inner polygons? Please, consider ...
1
vote
1answer
22 views

ArcGIS: segmenting buffer based on polygon corners

I have hundreds of square polygons which I've created a single continuous buffer around the polygons. What I'd like to try and do is try and break this buffer down into segments based on the corners ...
1
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2answers
57 views

How do I create a polygon based on a single point?

I have been given a large spreadsheet of sample data where each point coordinate represents the end of the sampling extent. I am tasked to represent these points as a sampling extent of 100' x 8' with ...
1
vote
1answer
26 views

Tool to set the maximum shape area of drawn polygons [ArcGIS 10]

Is there any tool or method to define beforehand the maximum area of each drawn polygon class ? Polygons are going to be distributed according to my idea so I need to have control over the process. I ...
2
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0answers
42 views

Is there an R package for finding the maximum-area rectangle in a non-convex polygon?

Does anyone know if there is an R package out there with an algorithm which finds the largest rectangle within non-convex polygons? I have Googled, searched the R Sig Geo archives, and looked here on ...
2
votes
1answer
60 views

Polygons between contour lines in QGIS?

I am trying to create polygons between contour polylines within a defined area (for which i have both polygon and polyline shps) but I seem to be thwarted at every turn. Using QGIS 2.14, I am sure it ...
3
votes
1answer
55 views

Polygon made by colour difference

I need to analyze differences (historical) in coverage of some species (seagrass Posidonia). Although its a marine species, subject area is very shallow and even from common satellite and aerial ...
3
votes
1answer
28 views

How to obtain attributes of a point layer that falls within a polygon layer of different CRS

I have created my own vector grid polygons in QGIS 2.12.2. This creates a new layer to my project, but it's projected in a "generated projection". I want to view the attributes of points that fall ...
2
votes
1answer
490 views

QGIS 2.14 GRASS geoalgorithms don't work?

I instaled qgis 2.14 and grass geoalgorithms dont work. Only 160 geoalgorithms and should be 168. MsBox: Missing dependensy, It seems that GRASS is not correctly installed and configured in your ...
3
votes
1answer
43 views

polygon split with predefined area

I am trying to split an irregular polygon into 120 equal area blocks. I also need a buffer around each new block within the polygon. Is this possible in QGIS 2.12.1?
0
votes
1answer
48 views

Closing out a 'add polygon' operation in the interactive MapWinGIS ShapeEditor

I am creating a small app that uses a MapWinGIS control and allows a polygon layer to be edited. Users can add/delete/edit polygons. All is working fine, but the operation to finish a new polygon ...
0
votes
1answer
219 views

How to copy closed loop lines into polygon feature class

I'm trying to utilize line contour data to find the volumes of local depressions. To do this, I want to copy the closed loops formed by depression contours into a polygon feature class to find the ...
6
votes
3answers
4k views

How to subtract (erase) polygons from polygon?

I have two polygon layers, one is green that represents all non-public right-of-way land. I have another polygon that is just a circle with a specified radius. I would like my output to be a polygon ...
2
votes
0answers
42 views

How can I create a grid of polygons from a .csv file or line vector in qgis?

I have a map defined by two seperate reference systems: one is a standard grid coordinate system, the other a series of irregualar polygons. I want to find which polygon each grid square overlays, and ...
13
votes
6answers
13k views

How do I create a convex hull in ArcGIS Desktop?

I would like to be able to create a convex hull in ArcGIS Desktop 9.x, but I cannot find an appropriate tool. How does one go about creating one? I am interested in answers for all license levels: ...
3
votes
1answer
68 views

QGIS 2.12 Lines to Polygons not work properly

In QGIS 2.12.3 I have a small shapefile with lines (as often occurs in parcel boundary datasets) of 2 vertices each, snapped to each other (no topology errors, no dangles, no intersections). But the ...
9
votes
5answers
18k views

Creating polygons around extent of similar points using ArcGIS Desktop?

I've millions of points collected for lithology layer. They have used a coding for different types of rocks. I need to create a polygon around the extent of similar points. What is the easiest ...
4
votes
0answers
265 views

Building larger polygons from smaller ones *without* common ID in PostGIS?

I am looking for a method, using PostGIS, of reconstituting a set of polygons from tens of thousands of smaller polygon 'pieces'. This is a simplified example, with the pieces shaded: ...
1
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0answers
37 views

Calculate obstacle accountability area in QGIS

Still being new to the whole GIS world, I am trying to calculate a regulatory takeoff obstacle accountability area for a given runway. For my case, this is defined as an area as follows. At the start ...
2
votes
1answer
265 views

How to construct semi-circle-shaped areas of confidence in ArcGIS Desktop?

We have polygon maps of river-bottom type and are interested in determining if particular bottom-feeding fish prefer one bottom type over another. We locate an acoustically tagged fish at a point in ...
1
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0answers
42 views

QGIS polygonize tool not working [closed]

I am having a problem using QGIS ver 2.10.1 Pisa. I am trying to use the polygonize function on a raster .tif image, and it runs, but only produces a thin sliver of polygons at the top, then stops ...
1
vote
1answer
67 views

How to use QGIS plugin “Rectangles, ovals digitizing tools”

I installed the Rectangles, ovals digitizing tools-plugin, found it on the toolbar, but it's inactive. I made a layer to which I want to add rectangles, it's visible and editable... The plugin bar is ...
3
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0answers
97 views

How to create a Polygon around a Linestring as a GeoFence in C# .NET

I'm looking for a .net library that will help to create a polygon that I can use as a Geo-fence around a route on a map. The following image demonstrates the result I'm after. Imagine that this ...
3
votes
0answers
44 views

Creating 30 areas with equal amount of road in an irregular polygon

The result should be something like this just more polygons. Does anyone know about a tool, which given a table, can create a number of polygons which will divide the tables object into, for ...
2
votes
1answer
92 views

Python script outputs polygon feature class with no shape_area or shape_length and therefore doesn't show up in arcmap

I am trying to copy features a number of times based on a numeric field value. The code below works for points when the POINT type is chosen. However, when I switched the feature type to POLYGON it ...
3
votes
1answer
331 views

Dynamically drawing a polygon around another shapefile, ArcGIS 10.2

Let's say I have a vegetation raster that indicates the density of forest all over the world. I also have a shapefile that contains the admin boundaries of each country in the world. The easy part is ...
0
votes
0answers
25 views

A vector object not being replaced in temp folder when using 'for' loop in R

I am currently running GRASS GIS through R interface and got stuck at this point; where I am using a 'for' loop in R, and the code is as follows: for(i in 1:nrow(Snapped_SSP_DSN)) { ...
0
votes
0answers
129 views

CSV to Polygon.SHP with Python

I'm looking for a way to convert CSV file to polygons shapefile. I need to make polygons with defined size. In the CSV file, The first row is the length of each polygon and the first column is the ...
0
votes
1answer
53 views

Capturing an event On Sketch Finish in ArcObjects

I am using IEditEvents_Event and IEditor. I invoked the GarciaUI_CreateNewFeatureTask and used: pID.Value = "esriEditor.SketchTool"; pCommandItem = pCommandBars.Find(pID); if (pCommandItem != null) { ...
1
vote
1answer
152 views

Data frame to SpatialPolygonsDataFrame with multiple polygons

I have a data frame with a bunch of polygons, several points per polygon. How can I convert it to a SpatialPolygonsDataFrame object? Here's my data frame: > buildings_df lon lat ...
0
votes
2answers
1k views

Zipcode to Polygon/Boundry

Is there any API out there which can give me Polygon value for a zipcode? I really thought that it would be fairly easy for me given the number of Maps APIs out there. Either Google Maps API or ...
2
votes
1answer
466 views

How to create a JTS geometry with holes and islands?

I have a JTS multipolygon geometry created by an Polygon array: multipolygon = gf.createMultiPolygon(this.polygons.toArray(new Polygon[this.polygons.size()])); Those polygons can describe holes or ...
0
votes
1answer
64 views

Creating polygon features on scanned historical maps to measure areas in ArcMap?

I have a collection of historical scanned topographic maps from the 19th century that have already been georeferenced (NAD 1927). I'm uploading the maps as JPGs into ArcMap and would like to use the ...
3
votes
1answer
178 views

Create mosaic like Voronoi Diagram from disjoint polygons

The illustration below shows the problem: as in (a) I have a set of disjoint polygons, as geometries in PostGIS. I need something like (b), the "mosaic" of this set of polygons, building it by a ...
0
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0answers
57 views

Postgis poligonize. How to create polygon in postgis from linestring

I have a problem with the poligonization. I have a table that contains the my borderstones. The second table defines the next and previous point. It is important because these are attribute datas. ...
10
votes
1answer
459 views

Postgis - extrude a polygon

I want to extrude a polygon shape in postgis to create a pseudo 3D effect. To this end I have written a crude function to achieve it. This is very much test code and it creates a new Y vertice for ...
3
votes
2answers
529 views

Can't transform lines to polygons

I have a similar question to: How to join lines in QGIS for later using "lines to poly"? I have a line shapefile that I wish to transform into a polygon shapefile. After making some ...
2
votes
0answers
35 views

Creating lines from lonely nodes in a linestring table to closest point on another linestring table

I want to segmentate a country (denmmark) by using barriers such as larger roads, railroads and the border/ coastline as the delimiting lines of the polygonise function in QGIS. But as most roads and ...
2
votes
1answer
121 views

Python script: “points to polygons” skipped fourth vertex

Using ArcGis 10.2 I have a script converting the nodes of a net into polygons. The polygons should be either triangles or rectangles but the script doesn't build polygon as rectangle, skipping the ...
3
votes
2answers
63 views

How do I generate grid square polygons from a 5m DTM file?

For my dissertation I have collected point features as coordinates and want to relate their distribution around a lake to elevation to see if there is any pattern/relationship between them. I have ...
1
vote
1answer
41 views

Obtaining areas from overlapping polygons

Using ArcView 9. I have a data set of about ten thousand parcel polygons and a similar number of driveway polygons extending from a roadway polygon into the parcel polygons. My ultimate goal is to get ...
16
votes
3answers
3k views

Producing building shadows using ArcGIS Desktop?

How would you generate building shadows from building footprints? I have attribute values for the heights of buildings. So would preferably like to have the shadows' sizes vary based on that. The best ...
1
vote
2answers
147 views

How to select points within a certain distance from a line?

I have a file with a points layer and a lines layer. I would like to select only the points that lay within certain distance (a couple of meters) of the lines. Is there an easy way to do this? Or ...
1
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0answers
49 views

Creating Polygons of specific sizes

I am very confused! I have tried this afternoon to create a polygon of a set size, namely 30m x 1.8m. I need 33 of these set over a grid (which I have created on a vector layer). I've read ...
0
votes
2answers
57 views

creating a right angled rectangle on google maps from a line

I have an application where the user draws a line, then automatically the software should create a rectangle where the line intersects the midpoint of two adjacent sides of a right angled rectangle. ...