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
votes
3answers
263 views

Is there Shape Metrics Toolbox or equivalent for ArcGIS 10?

I need to compute the geometric properties (e.g. contiguity index, dispersion index etc.) of a series of polygons and I would like to use the Shape Metrics Toolbox. I am using ArcGis 10 and the ...
2
votes
1answer
86 views

Feature is a point or polygon

Im new to GIS and am just curious if there is an instance where a feature can be a point in one map and a polygon in another map and vice versa?
0
votes
0answers
68 views

How to properly import georeferenced .dxf hatches/polygons into QGIS?

I have a georeferenced AutoCAD-drawing (some district borders I vectorized with Illustrator from a raster image), saved as a 2004 ASCII .dxf-file. When I import the file in QGIS ("Add Vector Layer"), ...
5
votes
3answers
11k views

How to Merge/Dissolve Polygons By Common Attribute Field in QGIS?

I have joined corresponding Local Enterprise Partnerships table data into a polygon shape file containing UK Local Authorities. How do I Dissolve or Merge the the Local Authorities polygons by ...
0
votes
4answers
328 views

Fix Self Intersecting Polygons Manually

I are looking to implement a method to fix self-intersecting polygons by editing the vertex order. We want to take the polygon rings and re-arrange/add in vertices to make a valid polygon. This is ...
5
votes
3answers
10k views

Converting multiple lines into single line using ArcGIS Desktop?

I've no idea if this is basic or what but I have this data that contains multiple lines (forming a polygon shape). I want to convert those lines (multiple - each with a start and end point) to a ...
0
votes
2answers
51 views

How can I find internal overlaps in my polygon feature class ideally via modelbuilder tools?

I have a polygon layer containing "depth curves" for the making of a skin of earth kind of map. I want to check whether or not my feature class contain any overlaps internally between these polygons. ...
3
votes
2answers
169 views

Creating polygons from line segments using PostgreSQL and PostGIS

Is there a PostGIS function that creates polygons from multiple line segments? I want to convert the pictured thirteen lines to four polygons. All lines belong to the table "boundary" (gid, geom). ...
1
vote
0answers
39 views

Progress Bar gets stuck converting Lines to Polygons using QGIS?

I'm trying to convert lines to polygon using QGIS 2.8.1. I use Vector > Geometry Tools > Polygons to Lines. I always get the progress bar stuck on 90%, it can't get to 100%. Could someone ...
1
vote
0answers
48 views

Matching (joining) two slightly incompatible polygon shapefiles

I have two shapefiles that represent two slightly different zonings of the same area (municipality zoning and transport zones), about 3000 polygons each. Several smaller municipalities may form a ...
5
votes
2answers
3k views

Removing sliver polygons in ArcGIS Desktop?

I unioned 2 layers into 1 layer, and it created sliver polygons. I used the elimination tool to merge them with neighboring polygons. As as result, it merges all sliver polygons to only one polygon ...
0
votes
0answers
80 views

Grouping Analysis (Clustering) of polygons with streets as borders in ArcGIS?

I have a question about the Grouping Analysis Tool in ArcGIS. Is it possible to use streets as spatial borders for the groups? I want to group a city district autmatically with multiple attributes, ...
2
votes
0answers
126 views

Different obs. when I extract raster values from polygons in R

I have two raster layers with the same projection, extent and resolution: r1: class : RasterLayer dimensions : 33434, 89431, 2990036054 (nrow, ncol, ncell) resolution : 0.001447053, ...
0
votes
0answers
10 views

How do you snap polygons as you draw in QGIS? [duplicate]

I need to draw a long row of patient rooms for a hospital. I have the following plugins installed in QGIS 2.6: Rectangle Ovals Digitizing CAD Digitize I want to drag a set of polygons that aligns ...
1
vote
0answers
42 views

Sample points based on underlying polygon attributes

I have a point shapefile and I would like to sample those points (just like the "Sample" tool allows points to sample underlying raster) to receive a table with underlying polygon values (interested ...
1
vote
2answers
110 views

Is there any library can perform polygons buffering/ inflating/ merge/ overlap at server side?

I have a set of polygon data express in lat long. I would like to perform some tasks (polygon buffering, inflating etc etc ..) in server side and output the result to client side (client is a web ...
0
votes
0answers
25 views

Selecting polygons using another polygon? [duplicate]

Hi, How is the best way or fastest(if there is) of selecting polygons of a different shapefile using a polygon of another shapefile. exercise example: i want select all the light brown polygons ...
1
vote
0answers
63 views

Why does the transformation bring bad results?

I have this map which has a polygon drawn on it. For the background map I use a WMS via ol.source.TileWMS and the polygon uses a ol.source.Vector object. Normally my view projection is EPSG:31467 but ...
0
votes
1answer
303 views

How to create polygon feature class from UTM coordinates?

I am working to create a polygon from UTM coordinates. The script I am using fails with a "must be a sequence, not float" error: Traceback (most recent call last): File "F:/sample/clipTiles.py", ...
0
votes
1answer
36 views

Python error in polygon to raster conversion

I want to convert polygon to raster. I converted the dbf file ( "cntymam") to table view to make use in the conversion. I am getting a error that the parameters are not called and also with the grid ...
1
vote
1answer
81 views

Select points near polygon in Postgis

I'm trying to make a spatial query, but I think something is wrong with it: I have two tables, places (point) and cities (polygon) When I try to get the points within 500m to one point, there is no ...
2
votes
0answers
38 views

Redistribution of polygons: supplementing and filling the specific area with polygons with specific size

I'm studying the impact of green wedges (red outline on the figure) on weather parameters in Copenhagen area. What I want to do is check how spatial redistribution of future afforested areas enacted ...
1
vote
1answer
246 views

draw square openlayers 3

I am starting to convert old code of openlayers 2 to openlayer 3. In the old version you could make polygon shape based of the amount of sides like in the example below: ...
1
vote
1answer
72 views

Parts of geometry disappearing in QGIS export to Illustrator PDF

I'm having this issue with certain polygons when I export to PDF. Everything looks fine in QGIS, everything fine in print composer, everything fine in the PDF as viewed in Preview or Adobe Reader. ...
0
votes
1answer
128 views

How to scrape polygon data from web map?

for each value of parcel no: in http://www.ma-investment.gov.bh/bps_ppd_en/ the map generates polygons. I want to extract xy values corresponding to polygon shapes which i can convert to ...
1
vote
0answers
267 views

Geofencing: Query if a POINT is within a POLYGON

I am trying to use the following query to search if a point is within a defined POLYGON (aka a geofence I want to define): ...
0
votes
1answer
193 views

Intersecting Overlapping Polygons Individually in ArcGIS

Map Layers: -Census Tract Shape File w/Population Data -Set of Store Locations with 5 Mile Buffers (Significant Overlap Between Buffers) I have create feature layers for both and I am trying to ...
2
votes
2answers
1k views

Zonal Statistics as table creates output but some are Null

I have temperature as a raster file and different ecoregions of a province as polygons. What I want to do is calculate the mean temperature per ecoregion. I succeeded in doing this by Zonal ...
1
vote
1answer
49 views

Adjacency matrix from polygons in GeoJSON

I have a set of polygon features in a GeoJSON file. They are neigbourhoods in Chicago. I would like to produce an adjacency matrix A, in CSV format or any other form, where the i,j element of A is 1 ...
0
votes
3answers
137 views

Counting number of Raster Cells satisfying a criteria within a Polygon

I have a USA raster dataset, which assigns to each cell a value from 0-100. I also happen to have a USA county shapefile. I simply want a count of the number of pixels/cells in the raster data with ...
0
votes
1answer
29 views

Assigning values from one polygon to second polygon if located within first using ArcGIS for Desktop?

I have two layers of polygons. I would like to know if there is a way to assign a value from a polygon in the first layer to any polygons from the second layer that fall within that polygon?
0
votes
1answer
64 views

Measuring areas in WGS 84 [duplicate]

I started a QGis project with adding information layers from OpenStreetMap such as the streets and railways for a city. This data has WGS 84 CRS. After that, I made a shapefile with urbanized bodies ...
0
votes
0answers
45 views

Transforming GIS based XY data (polygons) so that they overlap in R

So I'm attempting to come up with the average shape of these polygon features as a part of my masters research. To do this, I want to run a shape analysis of GIS-based X-Y data using the shapes ...
0
votes
0answers
60 views

Clip Image by polygon and create memory raster

I need to write a code in c++ that can clip an image (4 bands) by using individual polygons in a shape file. I need to access the values of pixels (from all 4 bands) are clipped by a polygon. I do not ...
0
votes
0answers
91 views

Change SHP Projection to display on Google Map

I'm pretty new to GIS but not to programming, so sorry if this was already asked. I didn't find a solution not sure if I didn't quite understand everything about Projections and so on. I have a GIS ...
5
votes
4answers
2k views

Why doesn't the split tool return any records in the attribute table?

I've been trying to split a large land use shapefile using a set of study area polygons as the split feature, but when the function finally finishes running (the land use dataset is quite large), all ...
0
votes
2answers
51 views

Count objects in polygons

I have a .txt file containing the coordinate of the two polygons in the picture below as well as coordinates for each of the lines inside the polygons. Could anyone help to count each line inside ...
0
votes
1answer
348 views

Draw polygons from an array in OL3

I have an query that produces an array of coordinates like so: 95.61,38.60 95.22,37.98 95.60,37.66 94.97,37.65 (long/lat separated by "," and coordinates separated by a space). How can I use these ...
0
votes
0answers
48 views

How to convert points distribution toward surface information?

I'm working with QGIS 2.6 I have a points layer representing different bus and train stops. I applied a categorized symbology; each colour represents a class of value (field regarding time access ...
1
vote
1answer
219 views

autocad-map of real estates with own coordinate system and information to be converted to use it in QGIS

I have a question regarding CAD and QGIS, but unfortunately I don't have a clue of CAD. Here it goes: Real estates data has been mapped. There are several reference points surrounding the area. So ...
6
votes
2answers
273 views

Wrong $area from field calculator (QGIS)

The area of the polygons in a layer, calculated by the field calculator with "$area" is wrong (much too big) for some polygons. If I draw the concerned polygon again, the area is calculated correctly. ...
1
vote
2answers
139 views

Correlation analysis of two polygon shapefiles with nominal data

I am working on a research- trying to model vegetation types based on factors affecting their distribution. In that case I have observed a strong relation between vegetation and soil types, from just ...
6
votes
1answer
5k views

can I extract overlap of polygons within the same layer?

I am trying to extract the overlap of polygons that are within the same layer in 10. The layer came from a buffered street centerline and I'm trying to extract and delete the intersections from the ...
0
votes
1answer
32 views

How to convert a specific multipolygon to minimum polygons

I've got this kml file with one multipolygon inside. A link for the file are here multipolygon.zip My goal is to get a multipolygon with the minimum count of polygons with only outer border and ...
3
votes
1answer
52 views

Concentric Ellipses around polygons as a representation of density

I have someone who has given me a thumbnail of a map with some concentric ellipsoids placed in estimated high density locations for our business. One location has three, and two other location have ...
1
vote
0answers
60 views

QGIS, How to label a layer in different font sizes, shrink to fit in polygon or a multiple line label?

I am just trying to figure out how to label a polygon layer to fit its size in QGIS. or if its very long title should break in line and scale, i did some research but couldn't find anything helpful is ...
1
vote
0answers
35 views

QGIS Partitioning Regions

I have to polygon shapefile maps in QGIS that cover the same area. One with ~90 polygons (call them regions) and the other with about ~800 polygons (call them zones). I want to add a data column in ...
2
votes
4answers
963 views

QGIS Polygon precision

Is there a way to edit the precision of polygon points in QGIS so that each coordinate has the same number of decimal places? For example, the coordinate 23.18273917, -84.29172638491 would be ...
0
votes
0answers
31 views

QGIS - save vector poly layer into individual shp files? [duplicate]

Using QGIS v2.8.1, I have a directory of GeoTiff images. Using the raster ‘Tile Index’ plug-in (selecting “location” as the file index), I am able to create perfectly matched vector polys that I can ...
4
votes
4answers
621 views

ArcGis 10 - create polygons as % of original

Could someone help me with the following? I have a polygon shapefile and need to create new polygons, within the originals, as % of original area. I used buffer by field (Field= new area as %) but the ...