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comment Algorithm for determining points from given dataset that are within a convex hull defined by a subset of original dataset
Thank you so much+
Mar
19
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accepted Algorithm for determining points from given dataset that are within a convex hull defined by a subset of original dataset
Mar
19
comment Algorithm for determining points from given dataset that are within a convex hull defined by a subset of original dataset
Thank you I have made some progress, I could not have done it with out your help, than you
Mar
19
comment Algorithm for determining points from given dataset that are within a convex hull defined by a subset of original dataset
I have done (378, 110) (190, 130) ( 65, 365) (300, 100) (500, 425) (225, 395) (378, 110) and gotten dx [0] 125 [1] 110 [2] 78 [3] 122 [4] -275 [5] -160 [6] 125 dy [0] -235 [1] -30 [2] 10 [3] 315 [4] -30 [5] -30 [6] -235
Mar
19
comment Algorithm for determining points from given dataset that are within a convex hull defined by a subset of original dataset
I got lost a little when programing it, I am getting a inHullHalfspace matrix full of zeros, and already verified some angles...Where do you think could be the error?
Mar
19
comment Algorithm for determining points from given dataset that are within a convex hull defined by a subset of original dataset
Is formula correct as I have tested all by hand, and not getting correct comparison in if (dy[p] * (D[k].X - P[p].X) - dx[p] * (D[k].Y - P[p].Y) >= 0) inHullHalfspace[k, p] = 1; else inHullHalfspace[k, p] = 0;
Mar
19
comment Algorithm for determining points from given dataset that are within a convex hull defined by a subset of original dataset
What I understand is you are using cumprod[inHullHalfspace[k,:],2] as an AND to see if that coordinate is 1 for all points, however in a little test I am doing, I get a matrix composed almost by zeros, and I know it should at least contain 5 columns equal to 1...
Mar
18
comment Algorithm for determining points from given dataset that are within a convex hull defined by a subset of original dataset
You are creating inHullHalfspace Matrix that will contain 1 if point P(x,y) is inside hull and 0 otherwise, Is this correct? Also could you please explain a little more the instruction cumprod[inHullHalfspace[k,:],2] ? knowing inHullHalfspace is a matrix, then cumprod(A,2) returns the cumulative product of each row. However you are taking k...But I got lost here
Mar
18
revised Algorithm for determining points from given dataset that are within a convex hull defined by a subset of original dataset
edited title
Mar
18
comment Algorithm for determining points from given dataset that are within a convex hull defined by a subset of original dataset
@ErikMiehling I have tried to think on a solution, And best I could do is to fix all z in dataset to 0, so I would only need to get points inside convex hull in 2D...
Mar
18
comment Algorithm for determining points from given dataset that are within a convex hull defined by a subset of original dataset
@ErikMiehling well in fact the number of points would be n>=3 and n<= all points on dataset, I am interested on getting points inside this n points. The anwwer for last comment is Yes I would like to get all points inside that convex hull
Mar
18
comment Algorithm for determining points from given dataset that are within a convex hull defined by a subset of original dataset
I want to find every point in data set that is inside the convex hull of eight points (eight points are inside original dataset)?