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.

learn more… | top users | synonyms

1
vote
1answer
147 views

Create polygons from points representing the corner vertices (ArcGIS)?

I am on ArcGIS 10.3.1. I have a point feature class that represents the corner vertices of the polygons. They are located in a regular grid. The labels represent the OBJECTID. The points can be ...
8
votes
1answer
466 views

How exactly is the centroid of polygons calculated?

I would like to know how exactly QGIS Geometry tools -> polygon centroid is calculating the point coordinates. For example does it divide the boarder of the polygon into small points, take two pairs ...
0
votes
0answers
46 views

Union overlapping shapefiles (poylgons) and merge the attributes where overlap occurs in R

I have 30 shapefiles of overlapping polygons and would like to union them into one shapefile. The attribute table of the 30 layers is exactly the same (two columns, Type and Origin). A new polygon ...
0
votes
1answer
57 views

Inserting field-based hyperlinks in non-spatial tables

I am trying to insert field-based hyperlinks into a non-spatial table in arc 10.3. The idea is simple, open the table and click on the link. I am able to add hyperlinks to spatial fields, and click ...
2
votes
3answers
181 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 ...
0
votes
0answers
24 views

Add a point inside a polygon randomly

If I have a polygon and a set of points all contained within the polygon. How would I best add a new point to the point set such that:- a) it was contained within the polygon b) it was spaced at ...
1
vote
1answer
44 views

How do I perform a Union (as per ArcGIS and QGIS) in MapInfo

I am running MapInfo 15.0 and need to perform a Union of two polygon layers (i.e. combine the two and preserve all boundaries and associated attributes). I know there is some ambiguity over the term ...
2
votes
0answers
68 views

Is there a way to draw polygons with a fixed area?

I am looking for a way to draw polygons with a fixed area. I am currently mapping farming options on field parcels. Some areas such as buffer strips run along features like rivers and hedgerows so ...
1
vote
1answer
356 views

R solution for 'TopologyException: Input geom 1 is invalid' self-intersection error?

The 'TopologyException: Input geom 1 is invalid' self-intersection error which arises from invalid polygon geometries has been widely discussed. However, I haven't found a convenient solution on the ...
1
vote
1answer
63 views

What does double digitized polygon mean?

I know what is a polygon but when a polygon is said to be double digitized? I failed to find a suitable meaning of double digitized after googling. I understand double digitized means digitized ...
1
vote
1answer
78 views

What does v.distance calculate excactly?

As I am from an economics department, I am quite a beginner in QGIS. I read, that if I wanted to calculate the distance from a polygon to a point/line/other polygon, I should use the GRASS plugin ...
0
votes
1answer
34 views

Defining area of influence for origin-destination dataset (where destination is port) using ArcGIS for Desktop?

Starting from an origin-destination dataset for a given country, where the origins are city (points) and the destination are ports (points), how can I identify the area of influence for each ...
1
vote
0answers
17 views

How to show neighboring polygons and polygon in which point exists

We have a table which has polygon related data stored. For finding if a point (long,lat) is within that polygon I am using following query in mysql SET @vasantKunjSectorC = 'polygon((77.161266 ...
-3
votes
1answer
61 views

How to determine how many times an area was burnt? [duplicate]

In arcgis I want to find from various forests fires shp files how many times parts of a particular forest were burnt during the last 70 years. Is there a way to count overlapping polygons?
1
vote
1answer
49 views

How to combine multiple overlapping polygon shapefiles into 1 - retain top most layer

Working with ArcGIS 10.2... I'm looking at geological data and have 4 separate polygon shapefiles. They all fall ontop of one another like a stack. I need to create a single dataset from the four ...
0
votes
1answer
99 views

Looking for specific polygon boundaries of DMA regions

I am trying to create a map in CartoDB and I need 2 specific polygons for it. The regions are: DMA_id, DMA_Name 743 Anchorage, AK 744 Honolulu, HI I searched every source I have and those two are ...
2
votes
1answer
36 views

(openlayers) Adding styled polygons from predefined toolbar?

I'm looking for a solution where I could easily add differently styled polygons to a map? Styles should be as "options" so that user can select e.g. blue or yellow polygon. What different options ...
0
votes
0answers
24 views

Finding and labeling intersections between polygons on a shapefile

I have two shapefiles-- one is labeled islands, the other is unlabeled parcels of land on some of the islands. My issue is that I need to label the islands that have parcels of land. My instinct is to ...
2
votes
1answer
67 views

Deleting duplicating edges while creating grids from centroid points

I am creating a edge table (edges) from some centroid points table(centroids). The distances between the centroids are 0.25 horizontally and vertically. The query I used to create the edge table as ...
1
vote
1answer
59 views

Cut line with polygons?

How do I cut a single line with polygons (in several segments) so that each cut line take data from the polygons? Something like a centroid takes.
1
vote
2answers
240 views

Create Editable Layer ArcMap 10.2 Desktop

In ArcMap 10.2 for desktop, I wish to create an editable layer to add a simple shape to. As of right now, I have a basemap layer and my selected basemap. However, since the basemap layer is not ...
1
vote
0answers
22 views

Wrong shape type

I am from statistics, and I need to do a fast cartogram. But I am getting this error from ScapeToad: Error processing record (a):160 PolygonHandler.read() - got shape type 1610612760 but was ...
2
votes
1answer
92 views

Create geometry from a result of intersection [closed]

Split a polygon in half with an extended line public Ipolygon CreatePolyFromIntersection(Ipolgon polygonA, Ipolygon bounradyThatcontainsPolylgonA, IFeature lmark){ ...
3
votes
1answer
163 views

Extracting border between contiguous polygons using ArcGIS for Desktop?

I have a shapefile with polygons representing unique populations. I want to determine contiguous polygons in my shapefile, and then extract the border separating contiguous polygons as a separate ...
0
votes
0answers
74 views

How to reclassify raster data that falls within a polygon

Thansk for your response Okay so I will reword my question more clearly I'm currently using ArcGIS 10. My task is to map forest cover with the image classification tool. The problem is some of the ...
1
vote
2answers
75 views

Selecting MultiPart Polygons if there are buildings in at least two of the parts

my data situation: shape of polygons (some are MultiPart Poylgons) shape of building locations (Points) What I need: Select all polygons that have two ore more parts and contain one building or more ...
2
votes
2answers
75 views

Query Features in Certain Direction

I have a polyline that I would like to query features that are on it's left, right, top, bottom. I am not looking for the features surrounding it but for features that are on a certain location from ...
0
votes
1answer
39 views

ArcGIS: How to create polyline features from the southern delineations of a polygon?

This can be considered a follow-up question to what I've asked a few weeks ago in this thread: How to set a buffer only in a specific direction? Back then I was trying to set a buffer to several ...
1
vote
1answer
66 views

Problem creating polygon in a layer

I am working in c++ qt4.8.5 and api qgis 2.8.2 c++. In my application I had to put polygon to define attractive zone. I found a great post in stackexchange (86812). I have based my on this post and on ...
0
votes
1answer
58 views

Polygon overlap into new layer on CartoDB

New cartodb & PostgreSQL user here. I have two rows in cartodb table and each row has its own polygon. The two polygons have some overlapping area. How can I create a new polygon of just the ...
1
vote
0answers
56 views

Polygons within Polygons Spatial Analysis

I have a polygon layer of planning applications and I am wondering if anyone can give any advice and or has seen or written a blog post that might point me in the direction of creating relationships ...
0
votes
0answers
19 views

Creating regions (set of lat, lng) on map using other than ArcMap?

I'm writing a project for school and as a part of the project I need to tell if a certain point is within a given region (which is a polygon made of lat, lng tuples). So far I was working with ...
1
vote
0answers
32 views

How to recognise building type from polygons?

I have a number of building polygons which are extracted from the aerial images, along with their postal address. (The aerial images are not available in my case.) For example, the polygon of a square ...
6
votes
1answer
188 views

Deleting 'garbage' nodes after polygon dissolve

I work with QGIS 2.10.1 on Windows 7 (x64). I have dissolved polygons from an attribute value and the polygons geometries being not perfectly joined together, I get some 'garbage' nodes I need to ...
4
votes
2answers
84 views

How to export a polygon based on elevations using a DTM or a DEM

I have a LiDAR generated DTM and a DEM (accurate to 10x10 feet). I am trying to export a polygon within a boundary which includes all elevations below a specific number. Seems like this should be ...
1
vote
2answers
79 views

Fix Polygons to be true Rectangles

I got a featureclass polygon of 4 point polygons that delineate the coverage area of a georeferenced image; these polygons will later be map sheets. Anyway I discovered some of them are not true ...
0
votes
2answers
149 views

Error in saving polygon with openlayers-3 and geoserver 2.7?

I'm using OpenLayers 3.8.2. I have wfs layer. I insert a feature. I save this feature as follow(I use geoserver 2.7-SNAPSHOT in server side): var features = source.getFeatures(); var insertedArr = ...
2
votes
1answer
79 views

Constructing a simple zip code polygon map in CartoDB

I'm new to using CartoDB. I suspect that what I want to do is rather simple but I would love some guidance. I want to produce a map that depicts multiple layers, the first of which is simple zip code ...
1
vote
1answer
97 views

How to calculate overlap area of two polygons?

I am a beginner in the world of GIS. I have one table polygons with each polygon having north-east and south-west coordinates. And for every polygon, I need to find area of overlap with other ...
1
vote
1answer
24 views

Trying to create colour co-ordinated values on a map from data from a csv. file

I have a list of values for some data recorded via Magnetic susceptibility, I have these in a shapefile and want to try creating a colour map out of the values. The values that I'm using relate to, ...
1
vote
0answers
32 views

Toggling selected feature when using Node Tool of QGIS?

Does anyone know of a way, when using the Node tool in QGIS to edit a polygon, to choose or toggle which feature (within the same layer) is being selected if they share a boundary? It seems to just ...
1
vote
1answer
80 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 ...
5
votes
2answers
122 views

Polygon points to Polyline

I am trying to create a polyline from the points that I query from a polygon. I have a polygon, and I am getting its edges, casting them to segments, and then use QueryNormal to get the mid point ...
0
votes
0answers
31 views

Modifying attributes of a shapefile using java

I have a polygon vector shape-file in which each feature has an integer attribute. I want to update this integer attribute(for all features) programatically using java on regular intervals of time. ...
0
votes
1answer
126 views

Splitting all polygon features in a shapefile into smaller equal width polygons

I have a shapefile of thousands of polygon features, that i would like to break up into smaller pieces (i.e. break a square into 8 equal pieces). I have read all over these boards for the right ...
2
votes
1answer
87 views

Leaflet polygon (multi polygon) to CQL equivelent

I am using leaflet with geoserver. I want to set up a CQL filter to do an intersect but having an issue with getting the geometry from leaflet polygon to cql polygon. For instance, the feature has ...
2
votes
0answers
43 views

Prevent polygon feature (catchment) overlap for land-use extraction using QGIS?

My aim is to calculate catchments for around 150 points and to extract land-use variables for them. In order to do so I need a vector dataset where no polygons overlap. This, however, seems to be a ...
1
vote
2answers
33 views

Geographical Field Points of a Boundary

I gathered field points with a TOPCON hand held receiver. I saved the points as a shape file and brought them into arc map. I used the editor tool to connect the points and created a polygon. Is ...
1
vote
2answers
60 views

How can I move a set of polygons in ArcGIS Pro?

I am very new to mapping and I have loaded a set polygons from a shapefile into ArcGIS Pro. They appear correctly however they have clearly lost (or didn't have in the first place), their longitudinal ...
0
votes
0answers
17 views

Layering polygons over neighborhoods?

I would like to layer a polygon with 30% opacity using different colors over OpenStreetMaps or Google Maps like so: How might I go about doing that?