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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1answer
8 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
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1answer
24 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
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1answer
15 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, ...
3
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1answer
39 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 ...
1
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2answers
41 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 ...
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0answers
17 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. ...
1
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0answers
15 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 ...
0
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0answers
14 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 ...
1
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2answers
109 views

Using GDAL to get vertices of a multipolygon

I am successfully using GDAL to get the vertices of a polygon from a ShapeFile using .NET code. This link showed me how to do that: ...
0
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1answer
44 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 ...
0
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1answer
877 views

How to narrow the result from Nominatim with only cities and countries, no additional areas with the same name?

I'm trying to get WKT or GeoJson polygons of cities and countries from Nominatim (for example, Paris and France). I send a GET request but it returns me several results named "Paris" or "France". How ...
2
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1answer
29 views

Reclassifying a polygon using field calculator

I am trying to reclassify a polygon into three classes: 1 and 2 = 5 3 and 4 = 3 5 = 1 I have been trying to do this by calculating a new field in the attribute table but I am very ...
6
votes
1answer
351 views

Permanently setting polygon/polyline segment length using ArcGIS Desktop?

I'm trying to create a several hundred polygons in ArcGIS 10, each of which may have up to several hundred vertices. For consistency sake I would like each line segment in these polygons to be of a ...
2
votes
1answer
13 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 ...
6
votes
3answers
1k views

Order of polygon vertices in general GIS: clockwise or counterclockwise

Two days ago I asked a question about the internal storing order for the vertices of a polygon in ESRI shapefiles. That question was answered (Are polygons stored clockwise or counterclockwise in a ...
2
votes
1answer
202 views

Extract data from netcdf using a shapefile polygon in python

I need to subset data from a NetCDF using a specific shapefile. The data are sea surface temperature and ocean color at 1/4 degree resolution. I have 4 polygons describing the US. Northeast ...
1
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1answer
292 views

Updating Polygon Geometries in master shapefile with detailed boundaries using ArcGIS Desktop?

I have a shapefile which contains the approximate boundaries for sites that are being worked on (thousands) in polygons, each with a reference number and additional detail in the attribution. I have ...
3
votes
2answers
70 views

What percentage of polygon x is in raster pixel y, efficiently

I feel this is a competition worthy problem, due to its size. I would like to weight a set of raster pixels to the attributes of a set of polygons. To do this I need to know the proportion of each ...
2
votes
0answers
23 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
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2answers
28 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 ...
2
votes
1answer
193 views

neighborhood boundaries for Saudi Arabia

I currently have set of coordinates (lat,lon) that I would like to associate with neighborhoods or districts in Saudi Arabia. Therefore,I might be looking for neighborhood boundaries (polygons ...
3
votes
2answers
194 views

Clipping from a tiled LAS dataset with LASTools (for ArcGIS)

I have huge amounts of lidar data stored as tiled datasets per project. The "tiles" are separate LAS files based on our national map sheet setup (800 by 600 meter). To keep an overview of the data I ...
0
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0answers
41 views

Automate Polygon Inner Ring Removal [closed]

UPDATE TO THE COMMENTS: If the solution space is too big for you - then please provide a free version (GDAL or QGIS). This is input into a modeling package that just cannot handle it, so I am ...
0
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0answers
15 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?
1
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1answer
38 views

want to make all poygons have z values as 0

I have polygons which stores different z values as vertices in Arcgis. I want that all z values must be equal to zero. How can I make this possible??
2
votes
1answer
33 views

How to calculate the form (or shape) factor of a polygon?

I am using QGIS to calculate the form (or shape) factor of polygons following what Louf and Barthelemy did here: http://rsif.royalsocietypublishing.org/content/11/101/20140924 The form factor is ...
8
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6answers
6k views

How to remove only donut holes from polygons using ArcGIS Desktop?

I am using ArcGIS Desktop 10.0. I have a trick for removing the donut holes, which is converting the polygon to line and then creating polygon out of the lines and in the end merging all of them. ...
2
votes
1answer
360 views

Determine when I have crossed state line?

We are currently using the Google Maps API to get route information and total mileage but we would like to determine when we are crossing into a new state. When we return the route information we can ...
2
votes
2answers
43 views

QuickOSM returns no result

I am trying to download the polygons for the Umweltzone Heidelberg from OpenStreetMap using QuickOSM in QGIS. I queried by name as shown in the screenshot: The corresponding OSM script looks like ...
0
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2answers
42 views

How to Dissolve Polygons Inside a Feature Class Based on Attribute Conditions

I have a large shapefile (saleArea.shp) which includes hundreds of small adjacent polygons. I would like to dissolve the polygons based on some conditions from tValues field into 5 bigger groups like ...
1
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0answers
32 views

How to show two layers at the same time in Qgis

I have a question about Qgis layers. I want to see two layers at the same times. one is lines which are boundary lines and the other is polygon which are district. when i was surfing about this ...
4
votes
1answer
34 views

Identifying a cluster of polygons based on attributes

I'm trying to identify a cluster of contiguous parcels that, when combined, add up to at least a given size and, when combined, have an assessed property value less than a given $ amount. I have a ...
2
votes
1answer
195 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 ...
1
vote
1answer
30 views

Extracting the closest Point to a Line within a Polygon using ArcGIS for Desktop

I have the following shapefiles: Polyline: Detailing a road network. Polygon: Containing approx. 2000 polygons enclosing sections of that road network. Point: Containing numerous (OS Addressbase) ...
0
votes
1answer
16 views

Intersection of two vector tables data in postgresql

I have satellite raster data is converted in to pixels using create table gtru_tile_pix as SELECT (ST_PixelAsPolygons(rast)).val, (ST_PixelAsPolygons(rast)).geom FROM ...
5
votes
3answers
2k views

How to interpolate into polygons using ArcGIS Desktop?

I need to interpolate values from points to polygons. I have a point shapefile and a shapefile of adjacent polygons. Some polygons get several points falling inside, some have nothing. I thought ...
0
votes
2answers
294 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 ...
0
votes
1answer
446 views

How to export to all points within Leaflet polygon?

Is it possible to export all points within a polygon drawn using Leaflet? (http://leaflet.github.io/Leaflet.draw/).
0
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0answers
19 views

Changing Polygon shape on Zoom in and Zoom out in google maps using javascript

In my application iam using google maps v3, on page load with default zoom level of 15 i load few polygons by passing points(latlng coordinates) from database on the google map now my question is when ...
0
votes
3answers
42 views

Is there any software or packages for creating 3D bar overlap city map? [closed]

Is there any software or packages for creating 3D bar overlap city map? More details: http://ny.curbed.com/archives/2015/01/09/3d_map_shows_where_nyc_housing_is_priciest_cheapest.php ...
4
votes
1answer
92 views

Creating shapefiles using textfiles in QGIS

I have a shapefile in QGIS which has polygons in it . There are several other attributes for each feature . I want to add another attribute to each feature . The value for this attribute is available ...
1
vote
1answer
50 views

Performance Improvement of Postgres vs PostGIS

I am trying to run the following query thousands of times per second to determine which is any polygon contains the passed in point. SELECT * from areas WHERE poly @> ? Poly is the name of the ...
0
votes
1answer
32 views

Multipolygon From Multilinestring PostGis

I have been looking for a answer for days. I dont even know if its possible. Tried: ST_AsGeoJson(ST_MakePolygon(ST_transform(geom,4326))) ERROR: Shell is not a line ...
0
votes
0answers
13 views

How to load points in a SQL server polygon table?

I have a spatial table in SQL server which stores both points and polygons geometry and I am using the table to return geoJSON for API calls. I want to load some points to this table with shapetype ...
1
vote
1answer
31 views

Convert Postgresql Polygon to PostGIS POLYGON

I have an existing table in postgres which contains a plain old posgresql polygon. I have added a new column using SELECT AddGeometryColumn ('public','fences','geom',4326,'POLYGON',2); I would ...
1
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0answers
22 views

Collect near polygons [closed]

I have the following data: The data have 5 level (in tones blue). I want to collect only the nearest polygons with the same level and sum the number (represent client number). When I collect only ...
1
vote
2answers
267 views

How to resample polygon vertices so that they are evenly spaced in Arc 10

I have digitized the outline of many river channels (by both manually picking points and using streaming mode), but now I need the vertices to be evenly spaced (for input to another program). I tried ...
0
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0answers
22 views

Intersecting polygons to a focal polygon with the same cell ID and also obtaining the length of the joining edge

I have a series of polygons, where there is a focal polygon (a type of coral reef). The other polygons are cut to the centroid of a cell where the focal polygon is included. The cell ID is given by ...
0
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0answers
12 views

how to use st_intersection() with re-projection in POSTGIS?

This is a shipping route from 'portland to busan' and I want to check the route against land_polygons like how much distance is traveled by a route through land.And the problem is while checking the ...
1
vote
1answer
92 views

CartoCSS: labels along inside of polygon boundary

I'm using CartoCSS to render maps that include large polygons (like national parks). At higher zoom levels I want labels along the inside of the polygon boundaries, like in OpenStreetMap: I ...