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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4
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1answer
83 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, ...
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0answers
44 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 ...
0
votes
1answer
48 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 ...
1
vote
1answer
63 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 ...
0
votes
2answers
60 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 ...
1
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1answer
97 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 ...
1
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1answer
137 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
121 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
36 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 ...
1
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0answers
11 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 ...
0
votes
1answer
184 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 ...
2
votes
1answer
70 views

Polygon split with defined area

I have polygons with interpolated data like on the picture on right. Now I want to split this polygon into smaller polygons with predefined similar area. Positions of these smaller polygons must be ...
3
votes
1answer
168 views

How to create a Color Ramp for Polygon Outlines in ArcGIS-Desktop?

Within the properties (symbology tab) of ArcGIS-Desktop (10.2.2, ArcEditor license level), is there a way to color the polygon outline of a layer using a color ramp? Using predefined color ramps ...
1
vote
1answer
217 views

Split a polygons into many polygons based on points using ArcMap

I have: A polygon feature that is a national park boundary, A multi-point feature that are security guard posts (number = n ) of the same park. I want to divide the national park area into 'n' ...
0
votes
1answer
90 views

Match polylines up to polygon

I'm trying to match polyline layer features up to polygon edges in a different layer quickly. I have a huge extent of polygons (river) and separate lines (bank features) that I need to get to ...
4
votes
1answer
78 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
2answers
114 views

Average width of irregular polygons QGIS 2.12.0 Lyon

I'm interested in examining the average width of streets, that are irregular polygons, for a project. I'm using QGIS 2.12.0 Lyon, and have lines (power cables) and Polygons (streets) as layers. For ...
1
vote
1answer
35 views

Create Polygon with 50'000 vertices

Is there a way to automatically create a new polygon in an existing Feature Class with over 50'000 Vertices? I work with ArcGIS 10.2 and FME. Hints how to create such a polygon within ArcGIS Desktop ...
3
votes
2answers
64 views

Splitting up selected islands using ArcGIS for Desktop?

What I'm trying to do is to split up that selected islands as single-part features/ polygons. But not all of them, you can see some little dots around the islands are like a part of the island. So ...
2
votes
2answers
79 views

Close Slivers in Polygon

I am creating polygons from a text file and am having trouble with the polygons crossing the 180 degree line. The issue is creating rectangular polygons with a sliver cut out of it as seen here: I ...
0
votes
1answer
82 views

How can I draw a polygon with a fixed area in ArcMap

Is there a way to draw a polygon with a fixed area in ArcMap? For example, I'm trying to create a 40,000 foot boundary around a feature, but the boundary does not have to be any specific length or ...
1
vote
0answers
31 views

Point and Polygon Data refusing to display: corrupt data?

I have two sets of shapefiles, one point data and one polygon data. Both were sent as part of a bigger set of data. Neither the point or polygon data will display when loaded into QGIS. The raw data ...
2
votes
0answers
35 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 ...
2
votes
0answers
26 views

Tool to help us re-district?

I work for a mid-sized school district and we unfortunately have to close one of our school buildings. That means that the neighborhoods who've been sending their children to the school that is ...
1
vote
1answer
47 views

Assigning a value to a polygon cell

In ArcMap 10.3 I have a raster file with a polygon grid overlayed on it: If the pixels in the colored raster have values such as blue = 5, yellow = 1, green = 3 etc, is there a way to output a table ...
0
votes
1answer
94 views

How to convert a line shapefile to a polygon shapefile? [duplicate]

I am using Arcgis 10.1 and have an existing line shapefile that i would like to convert to polygons.
5
votes
2answers
163 views

Find lower left corner of a rotated polygon

I am currently struggling with a mathematical problem and can't seem to get it solved. I have a bunch of rotated rectangular polygons (solution should also work for non-rectangular polygons) in ...
1
vote
1answer
47 views

How to determine which points fall within a certain value in a polygon in QGIS?

I have a shapefile that contains different levels for food security. On top of that, I have mapped points for certain office locations. This is shown below. The country shapefile is extremely ...
2
votes
3answers
101 views

How to split a polygon by a polygon using PostGIS?

I've a large polygon (table_a) that contains a smaller polygon (table_b). Now I want to split the larger polygon by the smaller polygon. Unfortunately st_split(table_a.geom, table_b.geom) isn't ...
0
votes
0answers
124 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 ...
11
votes
1answer
364 views

Is there ArcPy tool for polygon resizing like Scale tool of Advanced Editing toolbar in ArcMap?

I am writing a python script for ArcGIS 10.3. I know about Scale tool in ArcGIS interface but I can't find such arcpy command. It exists? As you can see on the picture the Scale tool works different ...
2
votes
2answers
225 views

Using one polygon from feature class as clip feature in ArcGIS for Desktop?

Using ArcMap 10.3, I am trying to clip some features using a polygon containing many census boundaries. I only want a specific census area as the clip feature, so I only have that specific shape ...
1
vote
1answer
35 views

Is there any site where I can found city shapes in postgreSQL polygon format

Is there any site where I can found city polygon area (for postgreSQL or similar)? I don't know if such resources exists, and I don't know how to find it.
0
votes
0answers
47 views

Spatial results tab saying:One or more spatial objects were too large to display

I've saved country borders in my sql server 2012 as geography data from geojson files. It turns out that when I query all the boundaries that have an administration level 2, not all the polygons are ...
1
vote
2answers
57 views

Clipping a SpatialPoygonsDataFrame to another SpatialPolygonsDataFrame

How do I restrict a SpatialPolygonsDataFrame so that none of the polygons lie outside of an "underlying" SpatialPolygonsDataFrame? The application I have in mind involves Voronoi Polygons a la Carson ...
0
votes
1answer
98 views

Clipping raster in PostgreSQL?

I want to clip raster (SRID 32649) with polygon(SRID 4326) into SRID 32648 First I transform raster using query create view ras68 as select st_transform(rast,32648) as rast from ras69 Then cutting ...
1
vote
0answers
29 views

Split Polygon Layer by other Polygon layer in QGIS

I know there is a lot of previous posts to this subject, but I simply cannot find the solution I am after in the other posts. I have to following problem: I have two very extensive polygone layers, ...
2
votes
1answer
422 views

Calculate area of polygons using OGR in python script

I have a shapefile of many thousands of polygons. I'm trying to append an area field to the attribute table and calculate the area of each polygon (in sq. meters) driver = ogr.GetDriverByName("ESRI ...
0
votes
1answer
51 views

cannot get properties of multipolygon - mapbox/leaflet

I'm currently using mapbox with natural earth and geojson to populate a map with multipoygons and custom markers. Each of these has a set of properties and information that I need to display on click ...
2
votes
2answers
123 views

GeoJson to Spatial Geography in sql server 2012, fix orientation of polygon

I've download from Mapzen many geoJson files related to countries with their respective administration level. Then I've parsed all the geoJson files and saved them to my sql server 2012 as geography ...
0
votes
1answer
114 views

R: problem with rasterize getCover - not working

Are there any known bugs with the getCover argument in the rasterize function? (R package 'raster'). or has anyone got a fix for the following: I have a series of landcover polygons, here is a small ...
2
votes
2answers
71 views

clip raster to polygon with 3 srids

I have 70 raster landsat images with srid: 32647,32648,32649 and want to clip raster to polygon (shapefile, srid: 4326) in postgis. I imported all raster into 1 table with parameter -s : 32648, ...
1
vote
2answers
83 views

Can one row in an attribute table be linked to many separate polygons?

Can one row in an attribute table be linked to many separate polygons? I did a series of selects, buffer, intersects on some shapefiles and my resulting table has for one row many polygons. Can this ...
1
vote
1answer
27 views

Setting final orientation of polygons in CityGML model

I am converting shapefile model of buildings in LoD2 to CityGML. In CityGML really matter about poylgon orientation(Countercloskwise can be seen from outside, Clockwise from inside). I have problem ...
1
vote
0answers
33 views

Polygon overlay, calculating changes, in QGIS?

I'm trying to create a relationship file between two vintages of census tracts. (in this case, 2010 and 2013.) Reason being to load ACS (American Community Survey) census data and use weighted means ...
1
vote
0answers
23 views

Showing polygon in OpenLayers Timeline?

I am trying to use the OpenLayers TimeLine library with a kml file. I used the available example for kml in github, but it shows points instead of polygon. How can I display polygon the TimeLine ...
0
votes
0answers
98 views

Google map's place polygons. How are they defined? Can we export them (batch preferably)?

I am working on a project that requires an approximate estimate of the area associated with a place (e.g. city boundaries). The places may be individual villages to country administrative districts. ...
0
votes
0answers
24 views

Spatial join between polygons and polygons using R [duplicate]

I'm trying to make a spatial join in R between two SpatialPolygonsDataFrame's. In more detail, I have zip code and electoral precinct shapefiles, and would like to know how they overlap, i.e., for ...
2
votes
1answer
129 views

Calculate The Minimum Distance from Polygon Centroid to Edge

I am looking to calculate the minimum distance from the Center of a polygon (A crescent shaped polygon would have a center inside the polygon) to its edge. I have parcel data and I am trying to ...
3
votes
1answer
167 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 ...