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Mar
20
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
awarded  Benefactor
Mar
19
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)?
Mar
18
revised Algorithm for determining points from given dataset that are within a convex hull defined by a subset of original dataset
added 440 characters in body
Mar
18
comment Algorithm for determining points from given dataset that are within a convex hull defined by a subset of original dataset
I was planning to make it easier fixing all z in dataset to 0, so problem is now how to get points inside loop (x,y)
Mar
18
comment Algorithm for determining points from given dataset that are within a convex hull defined by a subset of original dataset
Suppose I connected 8 points forming a loop (8 points are taken from dataset), Is it possible to get points that are inside that loop, What can it be done?
Mar
14
asked Algorithm for determining points from given dataset that are within a convex hull defined by a subset of original dataset
Feb
27
asked How to go from linear “equality-constrained” least squares (LSE) to linear “less-equality-constrained” LSE
Feb
23
awarded  Notable Question
Jan
15
comment Approach to store result of intersecting $n$ planes
One idea is to intersect n planes every 3 planes (when n>3) and then intersect result?