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Questions tagged [point-in-polygon]

Algorithm for determining whether a point is inside a polygon. Normally calculated by counting the number of polygon line segments that a ray from the point intersects.

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How can I determine whether a 2D Point is within a Polygon?

I'm trying to create a fast 2D point inside polygon algorithm, for use in hit-testing (e.g. Polygon.contains(p:Point)). Suggestions for effective techniques would be appreciated.
Scott Evernden
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SciPy Create 2D Polygon Mask

I need to create a numpy 2D array which represents a binary mask of a polygon, using standard Python packages. input: polygon vertices, image dimensions output: binary mask of polygon (numpy 2D array) (Larger context: I want to get the distance…
Isaac Sutherland
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Check if geo-point is inside or outside of polygon

I am using python and I have defined the latitudes and longitudes (in degrees) of a polygon on the map. My goal is to check if a generic point P of coordinates x,y falls within such polygon. I would like therefore to have a function that allows me…
Federico Gentile
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How to draw a n sided regular polygon in cartesian coordinates?

I have been trying to figure out how to write a simple program to compute the x,y points for creating a regular polygon of n sides. Can someone give me some code examples that don't use preexisting functions that draw polygons? I want to understand…
alphablender
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geopandas point in polygon

I have a GeoDataFrame of polygons (~30) and a GeoDataFrame of Points (~10k) I'm looking to create 30 new columns (with appropriate polygon names) in my GeoDataFrame of Points with a simple boolean True/False if the point is present in the…
Kvothe
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Find Point in polygon PHP

i have a typical question with the Geometric datatype of mysql, polygon. I have the polygon data, in the form of an array of latitudes and longitudes, ex: [["x":37.628134, "y":-77.458334], ["x":37.629867, "y":-77.449021], ["x":37.62324, …
shasi kanth
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Determine if a point reside inside a leaflet polygon

Suppose I Draw a polygan using leaflet like in the follow demo: http://leaflet.github.io/Leaflet.draw/ My question is how I can determine if a given point reside inside the polygon or not.
Majdi Taleb
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Is it possible to determine if a GeoJSON point is inside a GeoJSON polygon using JavasScript?

Is it possible to determine whether a GeoJSON point at a given lat,lon lies within a given GeoJSON polygon using only JavaScript (either through d3, topojson, or any other way)? For example, I can draw a map showing countries in the UK based on the…
user5325596
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Check if point is in spatial object which consists of multiple polygons/holes

I have a SpatialPolygonsDataFrame with 11589 objects of class "polygons". 10699 of those objects consists of exactly 1 polygon, however the rest of those objects consists of multiple polygons (2 to 22). If an object of consists of multiple…
majom
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Polygon Touch detection Google Map API V2

I'm trying to figure out how best to do this, I have a map with one Polygon drawn on it. Since it doesn't seem as though the Google Maps API V2 has a touch detection on a Polygon. I was wonder if it is possible to detect whether the touch point is…
Dwill
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MySQL implementation of ray-casting Algorithm?

We need to figure out a quick and fairly accurate method for point-in-polygon for lat/long values and polygons over google maps. After some research - came across some posts about mysql geometric extensions, and did implement that too - SELECT id,…
zarun
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Extend MySQL implementation of PiP Algorithm?

I need to make a point in polygon MySQL query. I already found these two great solutions: http://forums.mysql.com/read.php?23,286574,286574 MySQL implementation of ray-casting Algorithm? But these functions can only check if one point is inside a…
Mike
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Mysql function MBRContains is not accurate

I have the following POLYGON (in the image you can see the area it covers) POLYGON((-74.05100448502202 4.7239278424321,-74.05092938316898 4.7241416902206,-74.04830618275201 4.7237460717602,-74.04643668306903 4.7234306460692,-74.04635688735101…
Oscar Gallardo
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Finding largest inscribed rectangle of a polygon with Shapely

I am trying to locate millions of points inside a half-dozen polygons. Here's my code: def find_shape(longitude,latitude): if longitude != 0 and latitude != 0: point = shapely.geometry.Point(longitude,latitude) else: return…
Martin Burch
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Node.js/Javascript library to test if point is in geojson multipolygon

Is there some library for node.js or javascript in general that provides a function to check if a coordinate is in a geojson multipolygon? I'm trying to create a small HTTP API that tells me which multipolygons (representing countries, counties,…
Van Coding
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