Graham's scan is a method of computing the convex hull of a finite set of points in the plane with time complexity O(n log n). It is named after Ronald Graham, who published the original algorithm in 1972. The algorithm finds all vertices of the convex hull ordered along its boundary.
Questions tagged [grahams-scan]
34 questions
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polygon based on perimeter points - oracle spatial
I've a table with points. I would like to create polygon based on this points and then return only these points which are on perimeter(exclude points which are inside a polygon) . Is there any easy way to do that on database level using SDO…
Marcin Erbel
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Graham scan c++ won't work
My code for the graham scan is not working, it is supposed to get the perimeter of the convex hull. It gets the input of n points, which can have decimals. The algorithm returns a value higher than the actual perimeter.
I am using what I understood…
Jordan Alexander
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text file with x y coordinates to empty Point2D[] array in Java
I want to read a file in Java and put the numbers from the file into the (x,y) coordinates of a Point2D[] array. How would I go about doing this?
my file looks like:
5 4
6 2
4 1
which are points (5,4) (6,2) (4,1).
m743290
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How to sort floating point coordinates with no elimination of coordinates?
I have a list of coordinates that should form a edges of a path which i need to get sorted. I am trying to use Grahams scan and have tried a couple of samples from:
GrhamsScan.cs
ConvexHull.cs
ConvexHull Algo
These codes fails for several test…
Steve Johnson
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