On a map, a closed shape defined by a connected sequence of x,y coordinate pairs, where the first and last coordinate pair are the same and all other pairs are unique.

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3
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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
0answers
29 views

Feature Layer parameter showing only Polygon Shapefiles

I have created a Python Tool in ArcGIS where most of the paramaters musts be ONLY Polygon Shapefiles. You can also look on my previous question: Filter the Feature Layer parameter in Python Script ...
0
votes
0answers
19 views

How to make match two same rasters after conversion "Polygon to Raster?

I am trying to convert two .shp files of polygons of same buildings but with different layers of values into raster. When I do conversion from polygons to raster it always generates bit different ...
4
votes
1answer
46 views

Find polygons that does not contain (any) polygons with PostGIS

New to PostGIS, I have a polygon layer of water catchment areas which are formed by the specific monitoring points along the river upstream. For example, on one river, there could be multiple areas, ...
0
votes
2answers
68 views

Remove lines from inside a polygon (shapefile) in r

I have this code which prints the Galápagos Islands. But inside the islands, there are lines that I want to get rid off. How is this possible in R? library(rgdal) library(ggplot2) URL <- ...
2
votes
0answers
18 views

layer styling switches after zooming in with no reason

Does anybody have an explanation how it is possible? I have a strange trouble on the following map. The surrounding land layer, which is only a one polygon layer and is styled normally like: var ...
0
votes
0answers
50 views

Dividing a shape in equal pieces?

I have data in Autocad. As you can see there's a buffer (purple) inside of the blue shape, I want to divide the blue shape to small equal pieces that have the same surface area. What I'm looking for ...
4
votes
1answer
59 views

Reshape polygon to boundary of other polygon

I have two polygons. The first one has a white background and brown boundary. To othr has the pink background. how is it possible to reshape to first polygon to the boundary of the other polygon?
1
vote
1answer
50 views

Joining multiple polygons inside a single polygon in QGIS

I need to somehow "join" information from two shape files: zoning - these are large polygons indicating the zoning code for a moderately large area, typically hundreds of separately owned parcels ...
2
votes
1answer
44 views

Grid with data table attached to each polygon

I'm trying to wrap my head around a request a colleague gave for some data visualization. She is performing field observations and for every observation, she is assigning a grid # that corresponds ...
0
votes
0answers
48 views

Showing city border in Google Maps using OSM data

What I want is a border like in Google Maps: In my solution, i use the overpass-turbo service to get all long/lat for a city. All works fine! But sometimes, borders will be rendered not correct. I ...
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 ...
1
vote
0answers
44 views

What to do with polygons that were created from a raster file? [closed]

I need some suggestions. I'm working in Arcmap 10.3. I used a NDVI landsat product to find patches of row crops. I then extracted these cells and turned them into shapefiles. I want to measure the ...
8
votes
1answer
399 views

How to smooth adjacent polygons?

I want to smooth polygons which share a common boundary. How can I smooth them so that the shared boundaries stay shared? I'm using Arcgis 10.3
1
vote
0answers
50 views

how to separate land-use type from rows to columns from one shapefile

i am new to using ArcGIS. i have one shapefile of land-use data (100 rows) that has different land-use areas for each neighborhood (which are 10 neighborhoods), what i want is to have one row for ...
0
votes
1answer
40 views

Unexpected results when using ST_Intersection for polygon features

I've to create a spatial intersection of two tables (poly_a and poly_b) containing polygon features. Is there any way to remove unexpected linestring results? CREATE VIEW poly_intersection AS SELECT ...
1
vote
3answers
122 views

Creating line from point based on intersecting line at 90 degrees to line in ArcMap?

I am using ArcMap 10.2/10.3 and I need to create lines from points, so I can split polygons at the created line, as per the image below. So I have to cut the polygon at a 90 degree angle to the line ...
2
votes
1answer
99 views

2D polygons with height attribute to 3D features for ArcGIS Online

I have a 2D shapefile made of many polygons representing buildings. Each polygon has a height attribute. The goal is to get these into ArcGIS Online's "Scene" feature, showing extruded buildings, ...
5
votes
4answers
77 views

How to change feature draw order in QGIS?

Probably a very basic question here, I want to change the draw order of a shapefile in qgis, how can this be done? As you can see in the picture below, only the "10" layer is shown, but since this ...
2
votes
3answers
63 views

How do I create random points only within a multi-part polygon and none outside?

I am currently using a shapefile consisting of an area smaller than the entire study boundary ie. I want this to to be my overall study area. I used a raster to polygon tool and converted it to a ...
3
votes
3answers
132 views

Where to find a polygon shapefile of countries, states and islands?

As often happens, the hardest part of GIS is to come up with clean shapefile with an attribute table. I need to create a choropleth map, but all I have is this: Domicile,Captives New Zealand,24 ...
1
vote
1answer
51 views

Applying Snap_edit to polygon Geometry Object

I have a project where I am modifying over 1 million polygons (representing tracts of land) to make them line up with the PLSS land grid. My process works (mostly) by cutting up polygons based on a ...
1
vote
0answers
28 views

How to assign a grid of point data to corresponding grid of polygons

I'm using QGIS 2/12.3 I have a point layer with modelled data on a 1km grid, each point has a value (0-5, modelling temperatures) and lies at the centre point of a 1km grid square. I also have a ...
1
vote
1answer
23 views

Vector to raster conversion: Gaps within the vector boundary

Is there a tool in ArcGIS that will make the output raster completely encompass the vector boundary? Somewhat similar to select by attributes where all overlapping features however minuscule is added ...
1
vote
1answer
255 views

Is it possible to use Leaflet.draw on a map in R?

I want to develop an application where a user can draw a line, polygon etc... I currently develop with R and leaflet package and I found that it is possible to work with Leaflet.draw under ...
0
votes
1answer
207 views

Open Layers: Get Coordinates of drawn features

Can someone help in finding coordinates of drawn features? I am using this example OpenLayers website. I need to be able to export drawn objects as set of coordinates. Posting the code from the ...
0
votes
2answers
27 views

Keeping attribute table when converting from polygon-based feature layer to grid layer

I am trying to transfer (or extract) attribute data from a polygon-feature class to point data. I can do this for a grid file using the Spatial Analyst-Extraction-Extract multi-values to points ...
4
votes
1answer
76 views

Altering elevation of specific cells in raster layer of QGIS?

I'm looking to alter the height of some cells within a raster and it's been suggested that I do this by creating a polygon layer and use that as a mask to alter only the heights of cells within the ...
1
vote
1answer
28 views

transformations from a sphere using R for raster and polygon data [duplicate]

I am planning on using the MODIS burned area products which were produced by Maryland University. These come as either polygons or rasters. In the user guide it says A shapefile version of the MCD45 ...
2
votes
1answer
38 views

How can I split a polygon by network line in QGIS?

I have a road network as line layer and a land cover as polygon layer, I want to find number of subpolygon for each polygon that divided by line layer in QGIS? I used union function in Geoprocessing ...
0
votes
0answers
40 views

Adding custom vertices to a Leftlet LineString / Polyline

I have a normal Leaflet Draw page here, when I'm not in editing mode I would like to have custom vertex icon in some of the vertices that will also respond to click events, showing a popup. I looked ...
1
vote
1answer
41 views

Highlighting selected polygon features without filling colors in QGIS while editing?

When editing in QGIS, how can I highlight the selected polygon features without filling them with colors i.e. just outline the polygon boundary?
2
votes
1answer
57 views

Create frequency polygon from overlapping features in another polygon

Mac 10.9.5; QGIS 2.8.4-Wien; history and unioned data, in GDA94, zone 55 here. I have a polygon of fire history with a number of overlapping features. I want to create a new polygon for fire ...
2
votes
1answer
17 views

WFS Filter performed before or after reprojection?

I'm trying to perform a WFS filter with a polygon in EPSG:3031, (the native projection is EPSG:4326 I think). And I'm aware that WFS/GeoServer supports reprojection on the fly. But will the features ...
4
votes
1answer
33 views

How to extract a buffer layer from a vast amount of individual buffers around polygons using ArcMap?

I have a vector layer containing nearly 8000 singlepart polygons. It looks like this: I want statistics on the area that is further than 2,5m away from any border. I thought I could do this by ...
0
votes
0answers
20 views

Extracting coordinates and climatic conditions of grids where species polygon overlaps with the climatic layer in R?

I have species’ shapefiles and climatic raster files. The climatic file is in 50 * 50 km equal area grid. Now, I want to calculate the climatic conditions in each grid cell where species polygon ...
1
vote
0answers
42 views

How to correctly rasterize a polygon which crosses 180E longitude?

I want to rasterize a polygon wich crosses 180E lon with gdal_rasterize. The polygon is in the WGS84 projection. I used the following command: gdal_rasterize -burn 1 -of GTiff -ot Byte -ts 1500 ...
2
votes
1answer
34 views

Catchment boundary polygon from catchment area raster

I am trying to generate a catchment area polygon from a digital elevation model. I am using SAGA tools in QGIS and used the Flow Accumulation (Flow Tracing) tool to generate a catchment area raster ...
3
votes
1answer
42 views

Is it possible to remove small polygons from Census Block shapefile?

I just pulled up a shapefile that plots census blocks (TIGER product) using Quantum and I noticed that there are well over 1000 small polygons that aren't census blocks that are (I assume) used to ...
2
votes
1answer
52 views

Polygons drawn in editable feature service through Collector cause reverse or negative geometry

I have been experiencing a very odd situation where polygons – when drawn in an editable feature service through Collector on iPad – will draw and save, then seconds later the geometry will be ...
1
vote
1answer
48 views

What is the easiest way to create rings from existing polygons?

I have been given a shapefile from a client that features pivots, yet they were recorded as 10 circles overlapping. The software my company uses requires that these polygons be rings that don't ...
1
vote
1answer
78 views

How to map geoJSON polygon from a url request in python

Using Python I have loaded json data from the url http://environment.data.gov.uk/flood-monitoring/id/floods and have found that the flood areas encoded as geoJSON polygons are displayed as url links. ...
1
vote
1answer
36 views

How to assign the attributes of the largest overlapping polygon area to each overlapping gridcell?

I am new to R, and I am trying to use it to calculate the areas of polygons that overlap with each gridcell, in order to assign the attributes of the largest overlapping polygon area to the ...
2
votes
1answer
56 views

Selecting many maximum points within polygons

I've got a point layer with three values such as high, age etc. and polygon layer with many forest area. What I want to do is to select the 100 maximum (highest) points in every polygon. I can't do ...
4
votes
1answer
59 views

Add column to point data of whether point falls inside polygon

This seems like it should be fairly simple, but have been having quite a bit of trouble. I am no expert in ArcGIS for Desktop I have: one layer of points, and 4 polygons, which partly overlap I can ...
2
votes
2answers
73 views

Drawing a polygon of a given area

First, I am using QGIS 2.8.2. I have GPS waypoints and satellite imagery and am trying to draw polygons. This is easy enough, but I need to make sure each polygon is 1ha exactly. Is there a way to ...
1
vote
0answers
21 views

Convert a polygon grid into an edge table

I'm working on a robotics project. I've got a rectangular grid (polygon shape file) that is a navigateable/routable region (i.e. I can travel anywhere in this grid). That is I took my bounding area ...
13
votes
4answers
264 views

How to create lines to visualize differences between polygon features in PostGIS?

I've a PostGIS table polygon_b with some polygon features. There is also a table polygon_a which contains the same polygons as polygon_b but with minor changes. Now I want to create lines to visualize ...
2
votes
1answer
51 views

Can't Find the Split selected features with selected line from another layer tool

I'm trying to split a selected polygon features with a selected line from another feature layer. I, however, can't seem to get the tool for this to show up in my advanced digitize toolbar. In ...
5
votes
3answers
102 views

Merge a list of spatial polygon objects in R

I have a list of spatial buffers (30000 buffers) that I built with the function lapply: buff.pts <- lapply(1:nrow(pts.prj), FUN=function(l){ buff <- gBuffer(pts.prj[l,], width=1000) ## 1km ...