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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6
votes
2answers
863 views

How to create zip code areas from point data?

I have a point dataset which has zipcodes for a certain region. This zipcodes have been marked on the basis of lat long collected. So each zipcode is repeated as it would be useful to show the region ...
2
votes
3answers
183 views

Error in merging 2 shape files of different geometry types

I am trying to merge two shape files ... Here are the links of two shape files Australian State & Territory State and Territory ASGC Ed 2011 Digital Boundaries in ESRI Shapefile Format ...
1
vote
1answer
82 views

Get all points with in some range of a point (or range of point) in MySQL

I have got a list of points and a fixed range (10m). So what I have to do is for each point I have to find all the points present in a table with the 10m range of the given point. For example: Let ...
0
votes
2answers
50 views

How to create circles starting with points and attributes (diameter, lat/long)?

I have a point shapefile with attributes (diameter, latitude and longitude). For each point in that file, I want to create a polygon (circle) described by those attributes. The new shapefile should ...
3
votes
2answers
60 views

Move leaflet polygon to given position

I have a circle and a polygon that I'd like to move to the user's local position. I managed to move the circle latLng but I can't find a way to do the same thing with a polygon. Can someone help me ...
2
votes
2answers
232 views

gDistance to determine closest point to polygon: does changing projection change results qualitatively?

I'm using gDistance from the rgeos package for R to find the nearest point to a polygon. The projection of both points and the polygon is +proj=longlat +datum=WGS84 +no_defs +ellps=WGS84 ...
4
votes
5answers
2k views

Simplify shapefile parcel layer

I have a very large shapefile with over a million parcels within it. The problem I am having is that the polygons representing each parcel are very jagged. What I am looking for is a simple and fast ...
4
votes
2answers
58 views

Get the 2 points immediately before and after a given point in PostGIS

In the picture below: The given point is C, I would like to select A and B, but not Z (which is closer to C than B but it's not immediately after in the LineString). Note that C is always ON the line ...
1
vote
1answer
81 views

How to properly draw and label overlapping polygons?

I would like to show overlapping polygons on a single layer. The polygons are coloured based on a property and labelled according to another property. The problem is then twofold: The polygons are ...
3
votes
1answer
37 views

Positioning labels in center of clipped polygons?

I am using ArcMap 10.1 and would like to label a polygon layer that i have clipped. It appears that the label is set for the geometric center of the polygon that falls outside of the clipping.
1
vote
1answer
32 views

Converting Multiple Polylines to Polygons

I have a shapefile for Parcels but the whole thing seems to be divided into polylines rather than polygons. I'm trying to create an existing land use map. I was hoping there is an easier way to ...
1
vote
1answer
75 views

Creating building footprints from LAS files

I wish to create building footprints from the classification in our LAS files. I have filtered out the building points, using the point cloud filter. But I now trying to join the outermost points of ...
2
votes
1answer
34 views

Error while executing v.rast.stats command in grass plugin in qgis

I have a vector polygon which I imported in grass. I also have a raster from which I have to extract the value. I ran v.rast.stats command in QGIS 2.12. The command was executed with error. The error ...
4
votes
1answer
1k views

Changing the scale (generalisation) in ArcGIS 10

I have 2 polygon layers, accordingly 1:10 000 and 1:500 000. I want to generalize the first layer from 1:10 000 to 1:500 000. I tried using Simplify polygon tool, and since these scales relate to ...
4
votes
2answers
54 views

Manually selecting colors for different polygons within layer in ArcMap?

There is a polygon layer with several polygons. They are displayed with some colour which can be changed simultaneously for all of them. Is there a way to manually select several polygons (without ...
3
votes
1answer
87 views

R - Programmatically convert raster stack in data frame based on polygon extraction

Sorry for cross-posting. I also posted this question at the R-SIG-GEO discussion list, but since I wanted to get as much feedback as possible I decided to post it here too. I am trying to extract ...
1
vote
1answer
110 views

Calculating coverage of vector polygon over other polygons?

I have a shapefile file that contains a LiDAR footprint and I'm trying to figure out how much a county is covered by the LiDAR footprint. Two separate shapefiles. The attribute table for the county ...
3
votes
1answer
38 views

Iterate polygon column in ArcGIS model builder

I have a polygon with many columns. I want to convert into raster. I could do it one by one. But I want to iterate for each column of the polygon by model builder or any other way. Here you can see ...
0
votes
1answer
52 views

Build a leaflet polygon(s) from GeoJSON feature(collection)

I find it quite practical to work with leaflet Polygon and it would be great to be able to build such objects directly from GeoJSON content. I did not find any Polygon constructor taking neither a ...
5
votes
3answers
77 views

Dissolve overlapping polygons in SAGA

I've got the following (2D!) situation of overlapping polygons: I would like to have the polygon border dissolved such that I have only one polygon left. I thought this was a definitive case for ...
1
vote
1answer
29 views

“polygon” on sphere postgis geography

I have a set of points defined by their longitude and latitude, and I would like to check if they lie within a "polygon" on sphere. By polygon on sphere, I mean area in between 4 lines going between 4 ...
4
votes
1answer
45 views

PostGIS point distance from polygon not 0 when on edge

I have a pretty simple problem: SELECT * FROM ST_Distance(ST_GeographyFromText('POLYGON((70 -40,70 -39,71 -39,71 -40,70 -40))'), ST_GeographyFromText('POINT(70.48 -39)'), False) returns ...
3
votes
3answers
110 views

How can I join two polygons that are within the same layer in QGIS?

I have two polygons in QGIS that are within the same layer and I want to merge them so they are not in two different polygons, which means that the gap between them sould not exist. How do I do that? ...
0
votes
1answer
90 views

OpenLayers 3 draw polygon to select features

I have a set of points on a vector layer and I am allowing the user to draw a polygon on another layer of the map. I want to select all the points inside the polygon. I have got this to work, but ...
1
vote
2answers
402 views

Calculating minimum/maximum width for overlay of two polygon strips in ArcGIS or some Opensource GIS

Is there some solution for calculating minimum and maximum width for overlay of two polygon strips? When I clip these strips the result is another strip with variable width about 1 km and 20 km long. ...
4
votes
1answer
75 views

Clipping raster file in ArcMap over the extent of polyline shape

I have a calculated raster file, overlayed on a shapefile with lines (like on figure) I would like to clip the raster in ArcMap (since it is an interpolation and out of the vector shape it is mostly ...
1
vote
1answer
48 views

QGIS Polygon edge style based on adjoining feature?

Is there a way to change the style of only PART of a polygon's border in QGIS? I would like one or two edges of certain polygons to render a different color, or not at all, depending on the type of ...
7
votes
2answers
306 views

Displaying legend item as polyline instead of polygon in ArcMap?

I am using ArcMap 10.1 and am trying to create a legend that will display a polygon layer as a single line.
0
votes
0answers
21 views

Geometry Location In Respect To Another Geometry

I am trying to figure out where a geometry is residing in respect to another geometry. My Image explains things better, I have Square nodes A, and B. and I have circle Child nodes X, and Y. I have all ...
2
votes
0answers
29 views

“Point in polygon” counts that respond to filters?

I have a list of addresses in one layer and a polygon layer of census block groups for the local town, all stored in postgis. I have a nice display right now that labels each polygon with a count of ...
4
votes
1answer
59 views

How to get the list of QgsPoint from a polygon Layer in pyqgis

I have a little question about how to manage the points in a layer. from qgis.core import * def run_script(iface): layer = QgsVectorLayer(layerType.Polygon+'?'+crs.psg_4326, ...
3
votes
1answer
34 views

How do I retain all attribute data when clipping two polygons in R? [duplicate]

I would first like to say that my question is very much similar to this answered one, but the proposed solutions don't seem to be working for me. I think that my question is slightly different, as I'm ...
0
votes
1answer
40 views

Reshaping automatic polygon edge based on reference layer using ArcGIS for Desktop?

i have two polygon layer, one for Region administrative"Reference layer", and the second is administrative border is governorates. Governorates border is not identical with Region border. So there is ...
2
votes
2answers
105 views

Identifying LiDAR tiles that are located within boundaries of AOI

I am attempting to replicate the process of creating digital elevation models from raw LiDAR data and have been provided with LAS files covering an approximate 530 square mile county area. However, I ...
1
vote
0answers
35 views

create polygons using 2 coordinates

I have a script that creates a text file containing the upper left and lower right coordinates of my geotiff files in the following format. TileName UpperLeftX UpperLeftY LowerLeftx LowerLeftY I ...
1
vote
1answer
50 views

Average of raster elevation based on polygon boundaries

I am attempting to extract and calculate the average height of buildings using LiDAR converted to raster elevation data. I've created a DSM to cover the entire area and I am trying to extract just the ...
1
vote
1answer
55 views

Finding the area of polygons within other polygons in R

Is there a function in R which will loop through a layer of zonal polygons (i.e. a polygon grid) and return the area of a second polygon layer that is contained in each grid cell? I have a layer of ...
6
votes
2answers
271 views

Deleting polygons smaller than certain dimension using ArcGIS for Desktop?

I've made a model in modelbuilder in Arcmap 10.3, what it basically does is creating polygons over open areas such as farm-lands, grass-lands, marshes etc that has a low slope. My challenge is that I ...
0
votes
0answers
94 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
2answers
42 views

Count the number of raster tiles in each polygon in ArcGIS

I have a raster from the TRMM 3B43 product that contains a grid of 0.25 x 0.25 tiles (in degrees). I also have a shapefile with a number of districts. I want to know how many raster tiles are included ...
7
votes
1answer
201 views

Find and destroy duplicate OSM multipolygon/polygons in TileMill/PostGIS

In OpenStreetMap there are sometimes multipolygons where attributes are present on both the polygon and the multipolygon relation, such as the Grampians National Park: ...
2
votes
1answer
74 views

Cutting Polygon in Two in ArcMap?

For ArcMap10: I know there are multiple way to do this, but I wanted to see what was the most efficient for this case, as I will be doing it repeatedly in my workflow. I have a .shp polygon layer with ...
0
votes
1answer
114 views

Spatial Join in R

I'm fairly new to using R for spatial work so bear with me. I have found questions similar to this but nothing that answers this question specifically enough for me to implement it. I have point data ...
0
votes
1answer
33 views

Polygon shapefile layer shows NoData for Identify in ArcGIS Desktop?

I have a soil survey polygon map with each polygon representing a soil type. If I examine the attribute table of the layer, I can see what each polygon represents. If I select a row in the ...
0
votes
0answers
9 views

How to calculate area percentage from polygons from one shapefile within another? [duplicate]

I'm working on a project where I have to create python code that takes land-use data and adds a percentage field for each land-use category in a Census Tract shapefile. I've been trying to work with ...
2
votes
1answer
1k views

How to convert a polygon to a grid of polygons using QGIS?

For example, the city of Rotterdam represented as a hexagonal grid.
7
votes
1answer
7k views

Joining polygons in R

I am wondering how to join spatial polygons using R code? I'm working with census data where certain areas change over time and I wish to join the polygons and the corresponding data and simply ...
3
votes
2answers
139 views

Rotation of polygon fill symbol using ArcGIS for Desktop?

In ArcMap (ArcGis 10.1) I'm trying to find a way to fill a polygon with a symbol in different orientations. Is it possible? Example: look at the red semicircles, I would like to do something like ...
4
votes
1answer
55 views

Weighting amount of overlapping polygons in postgis

I have two tables that I join in my existing workflow. One of these includes flood events (was a shapefile that has been imported to PostgreSQL), the other one is a grid that holds the amount of ...
2
votes
0answers
26 views

How can I measure the distance between many polygon features and either another polygon or a line in QGIS?

I often have to manually measure the distance between a single site and other sites around it, but obviously this can get long-winded and I feel like there must be a much more efficient way of doing ...